Questions Asked on
April 10, 2011

  1. math

    The formula T=2*pi*sqrt[L/g] gives the period of a pendulum of length l feet. The period P is the number of seconds it takes for the pendulum to swing back and forth once. Suppose we want a pendulum to complete three periods in 2 seconds. How long should

  2. Chemistry

    40.0 ml of an acetic acid of unknown concentration is titrated with 0.100 M NaOH. After 20.0 mL of the base solution has been added, the pH in the titration flask is 5.10. What was the concentration of the original acetic acid solution? (Ka(CH3COOH) = 1.8

  3. Chemistry

    Sodium carbonate(aq) + hydrofluoric acid(aq) ? What is the formula for the complete chemical equation?

  4. chem

    Which of the following pairs of substances, when mixed in any proportion you wish, can be used to prepare a buffer solution? (Select all that apply.) NaCN and HCN NaCN and NaOH HCN and NaOH HCl and NaCN HCl and NaOH I thought it was the middle three

  5. Geometry

    Part 1. The area of a circular pool is approximately 7,850 square feet. The owner wants to replace the tiling at the edge of the pool. The edging is 6 inches wide, so he plans to use 6-inch square tiles to form a continuous inner edge. How many tiles will

  6. Chemistry

    Assuming the density of vinegar is 1.0 g/mL ' what is the molarity of vinegar? (use the percent by mass of acetic acid to vinegar which is 5%.) The molar mass of acetic acid is 60.05 g/mol?

  7. chemistry

    A sample of methane gas, CH4, was collected over water at 25.0ºC and 800 torr. The volume of the wet gas is 4.36 L. What will be the volume of the dry methane at standard pressure? Voldry methane=_______L

  8. Calculus

    In a chemical reaction, substance A combines with substance B to form subtance Y. At the start of the reaction, the quantity of A present is a grams, and the quantity of B present is b grams. Assume a is less than b. At time t seconds after the start of

  9. physics

    Monochromatic light passes through two parallel narrow slits and forms an interference pattern on a screen. As the distance between the two slits is increased, the distance between light bands in the pattern on the screen will 1) decrease 2) increase 3)

  10. Calculus

    In a chemical reaction, substance A combines with substance B to form subtance Y. At the start of the reaction, the quantity of A present is a grams, and the quantity of B present is b grams. Assume a is less than b. At time t seconds after the start of

  11. math

    The sum of two squares of TWO consecutive even integers is 340. Find the integers.

  12. chemistry

    a 5.0 dm3 sample of oxygen at a pressure of 200 kPa and 2.0 dm3 sample of nitrogen at a pressure of 500 kPa are introduced into a 2.5 dm3 vessel. what is the total pressure in the vessel?

  13. Capital Investment and Financing Decisions.

    1)Find the present value of Rs. 2,000 due in 6 years if money is worth compounded semi-annually. (b) Ascertain the present value of an amount of Rs. 8,000 deposited now in a commercial bank for a period of 6 years at 12% rate of interest. 2)You are

  14. algebra

    A car rents for $40 per day plus 18 cents per mile. Your on a budget of $67 a day. What mileage will allow you to stay within your budget?

  15. Geometry

    Find the area of a regular hexagon with side length of 10 centimeters. Round to the nearest tenth.

  16. Chemistry

    What is the pH of a solution that is 0.40 M in sulfurous acid (H2SO3) and )0.22 M in sodium sulfite (NaHSO3-)? Ka (H2SO3) = 1.3x10-2

  17. Algebra

    solve step by step 0=-2(8t^2-32t+21)

  18. chemistry

    iron+sulphur together are a mixture of small grains yellow and dark grey.Its chemical symbol is 'Fe + S'.When it reacts with oxygen they create a new chemical substance; Iron Sulphide. What do you put for 'explain the reaction using the Big Idea of Energy?

  19. accounting

    A company purchased $4,000 worth of merchandise. Transportation costs were an additional $350. The company later returned $250 worth of merchandise and paid the invoice within the 2% cash discount period. What is the total amount paid for this merchandise

  20. Calculus

    In a chemical reaction, substance A combines with substance B to form subtance Y. At the start of the reaction, the quantity of A present is a grams, and the quantity of B present is b grams. Assume a is less than b. At time t seconds after the start of

  21. world history

    what are the pros and cons to fur trades in canada in 1600?

  22. Math

    Express in partial fraction.7x^2-18x-7 divided by (x-4)(2x^2-6x+3)

  23. English

    I tried to summarize my rephrase in a few words. Could you please check them? 1) Caliban is kept prisoner in a cave by Prospero. 2) When Prospero interrupts his meal, Caliban curses both Prospero and Miranda and hopes that they will get drenched with the

  24. trig

    3sin(2x)-2cos(x)=0

  25. PHYSICS - URGENT

    a ball of mass m1 and a block of mass m2 are attached by a lightweight cord that passes over a frictionless pulley of negligible mass. the block lies on a frictionless incline of angle theta. (a) draw the free body diagrams (b) express newton's second law

  26. Calculus (please help!!!)

    Consider a window the shape of which is a rectangle of height h surmounted a triangle having a height T that is 1.3 times the width w of the rectangle. If the cross-sectional area is A, determine the dimensions of the window which minimize the perimeter.

  27. MATH

    IF THERE ARE 24 GIRLS IN THE CLASS HOW MANY BOYS ARE THERE IN THE CLASS Y=3/8X

  28. Physics

    A 4.8-m-tall, 30-cm-diameter concrete column supports a 5.0×105 kg load. By how much is the column compressed?

  29. Calculus

    In a chemical reaction, substance A combines with substance B to form subtance Y. At the start of the reaction, the quantity of A present is a grams, and the quantity of B present is b grams. Assume a is less than b. At time t seconds after the start of

  30. geometry

    if x+y=11, y+z=14, and x+z=13, what is the value of x+y+z ?

  31. jordan high

    A sample of a gas at 0.63 atm occupies a volume of 324 mL. If the temperature remains constant, what will be the new pressure if the volume increases to 124 mL? new pressure=_____atm

  32. Calculus (please help!!!)

    Consider a window the shape of which is a rectangle of height h surmounted a triangle having a height T that is 1.3 times the width w of the rectangle. If the cross-sectional area is A, determine the dimensions of the window which minimize the perimeter.

  33. math-natural log

    Nuclear medicine technologists use the Iodine isotope I-131, with a half-life of 8 days,to check thyroid function of patients. After ingesting a tablet containing the iodine, the isotopes collect in a patient's thyroid, and a special camera is used to view

  34. Berkeley college

    -2(4x-7)=2x-5

  35. Chemistry

    Which of the following combinations will make a good buffer solution? 0.05 M H2CO3 + 0.05 M KHCO3 0.5 M HI + 0.5 M CsI 0.3 M NH4Cl 0.3 M NH4Cl + 0.1 M NH3 0.3 M NH4Cl + 0.1 M HCl thanks

  36. Math

    how do you solve::: the sum of two numbers is 3. their difference is 1. find the number.

  37. Geometry

    Rhombus ABCD has an area of 264 square units. If DB=12 units find AC. So far this is what I have- 1/2(264)=132 132/2=66 66-12=44units Is this the correct process?

  38. chemistry

    how to prepare 0.250l of 0.750 M HCL solution,startin with 2.00 M HCL solution. what volume in liter of 2.00m solution we need?

  39. marketing

    Discuss the universal functions of marketing and those functions that would apply to the products/services provided by a fictitious firm of your choosing.

  40. Chemistry (repost)

    Which of the following pairs of substances, when mixed in any proportion you wish, can be used to prepare a buffer solution? 1)NaCN and NaOH 2) HCl and NaOH 3) HCN and NaOH 4)HCl and NaCN 5) NaCN and HCN is the answer 1 and 5?? chem - DrBob222, Sunday,

  41. Physics

    A ramp, a pulley, and two boxes. Box A, of mass 10.0 kg, rests on a surface inclined at 37° to the horizontal. It is connected by a lightweight cord, which passes over a massless and frictionless pulley, to a second box B, which hangs freely as shown. If

  42. physics

    On a catapult, what determines how far a missile moves?

  43. calculus

    find the volume of the solid generated by the revolution of the cycloid x=a(theta-sin theta), y=a(1- cos theta) about its base

  44. CHEMISTRY

    HOW YOU PREPARE 30.0ML OF 0.800M HNO3 FROM A STOCK SOLUTION OF 4.OOM HNO3? WHAT SOLUTION IN ML OF THE 4.OOM HNO3 SOLUTION WILL YOU NEED?

  45. physics

    Persons A and B are standing on a board of uniform linear density that is balanced on two supports, as shown in the figure. What is the maximum distance x from the right end of the board at which person A can stand without tipping the board? Treat persons

  46. Algebra

    sqrt(55) -sqrt(1/55)+sqrt(5/11)=?

  47. physics

    imagine a flat, lightweight wheeled cart that's low to the ground and has well-oiled bearings. what would happen if you approached the cart, stepped onto it, and walked along its length at a constant speed? it would a) remain nearly stationary b) advance

  48. geometry

    find the area of the garden drawn below.

  49. Pre-Calc

    2-2

  50. poem

    i read this book named abduction and my home work is to write a poem about it but the problem is i don't know how to write poem ?

  51. Physics

    Does a bathroom scale measure mass or weight? If if measures mass, then how come it changes when you are on the moon?

  52. chemistry

    Could someone answer this question so I understand it. Id appreciate it. Click the link for the question. img_photobucket_com/albums/v712/DeadMan986/Q10_jpg _ in the link = .

  53. Physics please help

    The difference in potential between any two points in a field is the ___ required to move a unit of whatever is affected by the field between the two points. I need help with this. Could it be work? or energy? Please help

  54. physics help

    I need help confirming my answers: 1) The work done on an electric charge equals a) IR b)q/t c)Vq d) It I think it's C.(Vq) 2) The direction of an electric field is the direction that a ___ test charge will move when placed in the field. a)negative b)

  55. Algebra

    Perform the indicated operation and state the domain. Let f(x)=x-1 and g(x)=x+1 f(x) - g(x) Heres my work (x-1) - (x+1) x-x=0 and -1-1=-2 Answer =-2 because the x's cancel each other out. How do i find the domain when there is no x in the answer?

  56. Psychology

    prediction is to explanation as _ is to _

  57. statistics

    "Separate the data by company and do descriptive stats for each. Copy and paste into a Word document, formatting appropriately. “Appropriate” includes formatting to a reasonable and appropriate number of decimals, including a good, descriptive caption

  58. CHEMISTRY

    Determine the heat of combustion of acetylene (C2H2).

  59. physic

    can someone give me 5 examples for the conservation of the angular momentum , 5 for the conservation of the impulse , and 5 for the conservation of the mechanical energy , in sport , arts or in technique , or just give me a site to find these examples, but

  60. CHEMISTRY

    Determine the heat of combustion of acetylene (C2H2).

  61. calculus

    A region is bounded by the function y=2x^2+3 and the x-axis over the interval(0,2). Sketch the graph of the bounded region. Use the limit process to find the area of the bounded region. Explain the step in this limit process. Please explain all procedured

  62. Math 7th

    two more than my value is 6 what does this mean??????? Please help!!!!!!!!!!!!

  63. CHEMISTRY

    Determine the heat of combustion of acetylene (C2H2).

  64. CHEMISTRY

    Determine the heat of combustion of acetylene (C2H2).

  65. ap us history

    criticize my ap us history dbq question that i made for a project During the 1960s, the united states moved from indirect into direct involvement in the vietnam war in order to stop the spread of communism. In light of the following documents and your

  66. kind of etymology

    ok so for my etymology class im doing a report and oral presentation on trade names and their etymologies. One of the first things i talk about are how companies or people choose a name for their product or compnay. one of the questions that most companies

  67. Physics

    An 9.00-cm-diameter, 400 sphere is released from rest at the top of a 1.90-m-long, 20.0 incline. It rolls, without slipping, to the bottom. A) What is the sphere's angular velocity at the bottom of the incline? B) WWhat fraction of its kinetic energy is

  68. elementry algebra

    use the slope intercept form to graph the equation y=2x+2

  69. math

    The length of a rectangle is three less than three times the width. The area is 90ft^2. Find the width and the length of the retangle.

  70. English

    Can you please check if the following sentences are possible? Thank you. 1) Dr Kemp was writing at his desk when he heard a noise. He opened a window and looked towards the town. 2) An hour later he had finished his work. It was time for bed. He walked to

  71. math

    The product of two consecutive integers is two hundred forty. Find the two integers.

  72. English

    I forgot to include the very last sentences of the day. Thank you very much. 1) Every week a person in Britain uses three plastic bags. They are strong and don’t disappear. They can last hundreds, possibly thousands of years. 2)They are called white

  73. biology

    Is any one body type better than another?

  74. chemistry

    A 828 mL sample of NO2 gas is at STP. If the volume changes to 598 mL and the temperature changes to 12ºC, what will be the new pressure in atmospheres? new pressure=_____atm

  75. statistics

    what number is 16 percent of the variable y

  76. chemistry

    when we make CH3MgX first we take Mg in baloon.then we active it with I2 and finally we increase CH3Cl. we know product is very sensitive in air then we carry a mount of it with syring. Now how can we calculate molarity of product becouse we donot know

  77. geometry

    in a regular polygon, with center O, and a side AB, measure of angle AOB =72 degrees. If AB is 4.6 in. find the perimeter

  78. algebra 1

    factoring quadratic expressions 8x^2+32x+14

  79. Finance

    The Evanec Company’s next expected dividend, D_1, is $3.18; its growth rate is 6%; and its common stock now sells for $36.00. New stock (external equity) can be sold to net $32.40 per share. What is Evanec’s cost of retained earnings, r_s? What is

  80. Chemistry

    How many grams of nickel (II) sulfate hexahydrate would be present in one liter of a 0.40 molar solution? (Hint: a 1.0 molar solution would have 1 mole of NiSO4*6H2O per liter of solution)

  81. math

    Mary's group of close friends are going to fifth grade in September. All are going to Belleview Elementary and their homerooms will be room 12, 14, or 16. All of her friends but 4 are going o room 12, all but 4 are going to room 14, and all but 4 are going

  82. Physics

    A 20 kg rod is 3 meters long and is attached to the wall by a hinge at point A and is held at the angle indicated by cable BC. Find the force in the cable and the forces in the x and y-directions at the hinge A. (center of mass in middle of rod downwards)

  83. chemistry

    A sample of O2 gas was collected over water at 23ºC and 711 torr. What is the partial pressure of the O2? (The vapor pressure of water at 23ºC is 21.2 torr.) partial pressure of O2=______torr

  84. Calculus (pleas help I really need help with this)

    Consider a window the shape of which is a rectangle of height h surmounted a triangle having a height T that is 1.3 times the width w of the rectangle. If the cross-sectional area is A, determine the dimensions of the window which minimize the perimeter.

  85. physics

    A baseball player pops a pitch straight up. The ball (mass 160 g) was traveling horizontally at 32.0 m/s just before contact with the bat, and 24.0 m/s just after contact. Determine the magnitude of the impulse delivered to the ball by the bat.

  86. early childhood

    if anyone has the answers to exam 00382900 Facilities and staff. I would like you to review my answers. I can't post all of the questions of i would. 1.B 2.A 3.C 4.A 5.A 6.D 7.C 8.B 9.B 10.B 11.D 12.B If any of them are wrong please let me know so i can

  87. Physics-Please check

    I'm trying to find the gravitational force of an electron at earth's surface. I know I say Fg = mass electron * gravity Gravity in this case is 6.673*10-11 m^2/kg^2 correct, not 8.93 * 10^-30N that we used for force of acceleration, right. I use the

  88. geometry math

    If you put two dodecagons together with another polygon that will exactly surround a point what type of polygon could be used?

  89. Chemistry

    calculate the molar concentration of H3PO4 in the cola sample. Volume of decarbonated cola used 25.00mL, Molarity of NaOH used for titration 0.0100M, and Volume NaOH used at first equivalence point is 14.54mL.

  90. chemistry

    A 375 g piece of iron was heated to 975 °C and then quenched in a bucket containing one gallon of water at 20 °C. What was the temperature of the water after the iron and the water came to thermal equilibrium?

  91. Chemistry

    Earl N. Meyer found that it took 25.46mL of the 0.0100 M NaOH to reach the firtst equivalence point for the titration of 25.00mL of Zlot cola. What is the molar concentration of phosphoric acid in Zlot cola?

  92. sciences

    If a baseball is thrown 30 m/s backwards from a truck moving 50 m/s, how fast will the ball strike the glove of a ground-based catcher?

  93. chemistry

    A 375 g piece of iron was heated to 975 °C and then quenched in a bucket containing one gallon of water at 20 °C. What was the temperature of the water after the iron and the water came to thermal equilibrium?

  94. MATH

    1+1

  95. english

    Except for a few pigeons, Central Park was deserted. Mist hung above the chilled grass. Patches of old snow, scattered here and there, looked like white puddles. The sun hung just above the horizon, casting red and orange streaks across low-hanging clouds.

  96. please help... history/social studies?

    What important contribution did the Phoenicians make to world civilizations? !@#$%^&sntly, I don't know. How was htat contribution spread to other cultures?

  97. hsm210

    What are some concerns about the current state of the human service industry?

  98. MBA Executive : Banking & Finance

    Following are the financial statements for A Ltd and T Ltd for the current financial year. Both firms operate in the same industry. BALANCE SHEETS Particulars Firm A Firm B Total current assets Total fixed assets (net) Rs 14,00,000 10,00,000 Rs 10,00,000

  99. english

    poem of nature thha have mataphor,simile,persinofi

  100. MBA Executive : Banking & Finance

    1) The right under which an unpaid seller who is in possession of the goods is entitled to retain them until payment of the price is done is termed as....... 2)If the no of level investments be ‘t’, total no of level installments be ‘n’ and total

  101. english

    what is the topic sentence in each paragraph? 1. Alice Doe’s article discussed overlooked tax deductions. It talked about some of the most commonly missed deductions. Whereas her use of statistics seemed to bolster her arguments, it would have been nice

  102. English

    In the story "Oedipus" by Sophocles, do you think there was any way that Oedipus could have avoided his fate? How? In what way?

  103. Math

    Express in partial fraction.7x^2-18x-7 divided by (x-4)(2x^2-6x+3)

  104. maths

    the perimeter of an isosceles triangle whose base is 11cm is 39. one of the equal sides of the triangle will be: A 11cm B 9cm C 14cm D 12cm

  105. algebra 2

    A bag contains 8 purple marbles and 3 yellow marbles. Without looking, you draw out two marbles at the same time. What is the probability that the first marble is purple and the second marble is yellow?

  106. marketting ,,,,,,please help me asap

    please is any one can hel me to answer this question as soon as possible thanks a lot. question in the subject marketing. 1.what distribution decisions would a new firm RENTS VANS to small business, seasonal business have to make?

  107. Models for Health and wellness

    I couldn't think a of a country to use or assess for strengh and weaknessess

  108. English

    I need you to check these sentences for me on Prospero and Caliban. I'm not sure about the tense choice (can you say that)? 1) Caliban hopes that they both Prospero and Miranda get drenched with a dew as evil as the kind his mother used to collect with a

  109. physics

    You throw a ball straight up in the air. The instant after leaving your hand the ball’s speed is 30 m/s. Ignoring the effects of air resistance, predict how fast the ball is traveling 2 seconds later? Where is it at this time?

  110. English

    I forgot to add the following sentences on the same subject. Thank you. 1) At that time he loved him back. In his turn (In return for his kidness?)Caliban showed him all the features of the island: the freshwater springs, the saltwater pits, the barren

  111. English writing

    Hello! I have written an article about childhood's best friend. I'd be glad if someone can help me to correct my mistake or others. thank you Hello! I'm franch and I'm studying english. I have written an article about chilhood's best friend. I'd be glad if

  112. physics

    what will be the distance time graph for a train standing at a station?

  113. calculus

    In still water, Maria can paddle at the rate of 7 km/h. The current in which she paddles a speedof 4 km/h.At what valocity does she travel downstream? has

  114. probability

    1. The time it takes a student to cycle to school is normally distributed with a mean of 15 minutes and a variance of 2. The student has to be at school at 8.00a.m. At what time should the student leave her house so that she will be late only 4% of the

  115. Calculus please help!!

    Consider a window the shape of which is a rectangle of height h surmounted a triangle having a height T that is 1.3 times the width w of the rectangle. If the cross-sectional area is A, determine the dimensions of the window which minimize the perimeter.

  116. math

    HOW MANY 3GOIN TO

  117. English

    When I rephrased the speech between Prospero and Caliban (taken from the Tempest, Act I Scene II) I used the same tenses as used in the play. (simple present to refer to their current speech and past simple to refer to their past relationship). Why do I

  118. Math

    answer to travis has designed a rectangle with an area of 59 square units. his rectangle is the smallest rectangle with whole number side lengths. what are the length and width of the rectangle, explain your reasoning. what is the perimeter of the

  119. Math

    how would you graph x>-2 and how would you solve the sum of two numbers is 3. their difference is 1. find the number.

  120. physics

    At what temperature will ni=10^14/cm^3 in silicon? And ni=10^16/cm^3?

  121. Math please help!

    Nuclear medicine technologists use the Iodine isotope I-131, with a half-life of 8 days,to check thyroid function of patients. After ingesting a tablet containing the iodine, the isotopes collect in a patient's thyroid, and a special camera is used to view

  122. Transportation - Tires and Wheels

    Why is it important to remount a tire in the same position on a wheel?

  123. maths

    I am saving up to buy a car. Each week I save 25% of my salary of $624. If the car costs $13260 and i need 20% of this for a diposit,how many weeks must I save in order to raise this diposit? A 16 B 18 C 17 D 21

  124. chemistry

    how to prepare 280 ml of a 27% v/v solution of ethanol, C2H6O in water

  125. English

    Thank you for your explanations. I clarified the possessive adjectives as you suggested to me.I have problems with sentence 3 and with the words preceding the question marks. 1)In return for Prospero's kidness Caliban showed him all the features of the

  126. physics

    I have 2 fill in the blanks that I need help with. 1) When electrons are forced away from a/an ___ plate, work is done. could the answer be positive? 2) Any pointed or angular surface of an object must have a/an ___ concentration of charge to establish

  127. General Chemistry 2

    The molar heat of vaporization of benzene is 31kj/mol. Calculate the entropy change for the liquid vapor equilibrium. At 1 atm pressure, benzene boils at 80.1 degrees Celsius.

  128. English

    I forgot to include the following part. I really hope you can have a look at it, too. 1) But Caliban had bad blood in him, no matter how much he learned, and good people couldn't stand to be near him. 2) So Caliban got what he deserved, and was locked up

  129. English

    What are the meaning of good guys and bad guys?

  130. Geometry

    Rombus ABCD has an area of 264 square units. If DB =12 units find AC.

  131. physics

    imagine a flat, lightweight wheeled cart that's low to the ground and has well-oiled bearings. what would happen if you approached the cart, stepped onto it, and walked along its length at a constant speed? it would a) remain nearly stationary b) advance

  132. Geometry

    Find the area of a nonagon with a perimeter of 126 inches. Round to the nearest tenth.

  133. maths

    I am saving up to buy a car. Each week I save 25% of my salary of $624. If the car costs $13260 and i need 20% of this for a diposit,how many weeks must I save in order to raise this diposit? A 16 B 18 C 17 D 21 give me the answer which one A B C OR D

  134. Geometry

    Find the area of a trapezoid ABCD with verticles A(2,2) B(4,6) C(4,-3) and D(2,-1)

  135. english

    how do you start a good beggining of a story plz help

  136. Math

    How might you find the perimeter and area of rectangle that is increased by a ratio of 1:n

  137. chemistry

    Im stuck on this question. Could someone answer it so I understand it.Thanks When (R)-Butan-z-ol is treated with TsCl in pyridine and the tosylated alcohol is treated with sodium iodide in acetone, the resulting product is? A)(R)-2-iodobutane

  138. Math

    Camilles math teacher described a quadrilateral with 2 pairs of parallelvsides and 4 lineage of symmetry. Which of these quadrilaterals must have the characteristics that Camilles math teacher described? A. Trapeziod B. Square C. Rhombus D.parallelogram

  139. math

    Cindy bought 3 pounds of candy for $2.16. At this rate , how much would the candy have cost if she had brought only 2 pounds?

  140. Chemistry

    Given that the Ka of benzoic acid is 6.50 x 10-5, how would one prepare 0.500 L of a benzoic acid/sodium benzoate buffer of a desired pH of 4.00? The starting concentration of the benzoic acid is 3.00 M and the molecular weight of sodium benzoate is 144.10

  141. physics - URGENT

    Two blocks are connected by a heavy uniform rope with a mass of 4.00 . The topblock is 6.00kg, the bottom block is 5.00kg with an applied upwardforce of 200 N. What is the tension at the midpoint of the rope?

  142. physics

    Silicon is doped an acceptor of 10^18/cm^3. Find the electron and hole concentration, the electron and hole mobilities, and the resistivity of this silicon material at 300 K. Is this n-type or p-type?

  143. Math

    how do you solve: x+y=3

  144. physics

    Two 5.0 g spheres are suspended from a long thread and separated by a distance of 140mm. The spheres repel after being charged to +86nC. Find the angle

  145. chemistry

    Determine the heat of combustion of acetylene (C2H2).

  146. Chemistry

    Could someone answer this question so I understand it. Thanks Alcohols can function as both nucleophiles and as electrophiles in various reaction conditions. Which of the following statements is/are true? A)When R-O-H is a nucleophile, the O-H bond is

  147. chemistry-URGENT

    Hydrazine is used as a rocket fuel. When 1.50 g of hydrazine, N2H4, was burned in a bomb calorimeter, temperature increased from 23.57 °C to 28.84 °C. The heat capacity of the calorimeter was 5.510 kJ/°C. Determine the enthalpy of combustion of octane.

  148. physics ---- really dnt get this at all

    if friction is set to zero and on planet Earth. Now, if you attach a mass to the spring from its initial equilibrium position, it vibrates forever in simple harmonic motion. Why doesn't it come to rest after stretching by a distance 'd'; proportional to

  149. English

    Please read and check for any errors.Let me know what I need to change or add. I was debating whether ot not I suppose to underline American Literature Masterpieces.Thank you so much. _______________________________________ Would you be interest in owning

  150. Math

    At lunch, 17 students drank lemonade. This represented 20% of the student on the field trip. How many students were on the field trip?

  151. Geometry

    Problem : Howm do you find the area of a circle circumscribed about a regular pentagon with a perimeter of 50 inches. So far I each side of pentagon is 10. How do I find the radius of the circle? Is this the correct direction to go?

  152. all

    Can someone post questions from all subjects for eighth grade?

  153. Chemistry

    15 ml of 0.5 M of HCl is added to a 100 ml sample of 0.2 M HNO2 (Ka for HNO2= 4.0 x 10^(-4)). What is the equilibrium concentration of NO2- ions?

  154. calculus

    For x ∈ [−12, 10] the function f is defined by f(x) = x7(x + 1)4 On which two intervals is the function increasing (enter intervals in ascending order)?

  155. uniform motion science

    How would you set up the following unifor motion problem... How long will it take the plane to fly 1000 km (i mile=1.61 km) if it is traveling at a constant velocity of 80 km/hr.

  156. Geometry

    Find the area of a trapezoid ABCD with verticles A(2,2) B(4,6) C(4,-3) and D(2,-1). Should I use a graph and go from there? I'm just not sure of how to set this up. The book answer is 12units. I am not coming up with the answer

  157. Chemistry

    Could someone answer this question so I understand it. Thanks cyclopentanol ----> cyclopentane Which of the following sets of reagents could be used to accomplish the above transformation? a)TsCl/Benzene & LiAlH4 b)H2SO4 & H2/Pd c)TsCl/Benzene & KOtBU/BuOH

  158. Physics

    A bridge is 40.0 m. A car weighs 1.5 x 10^4 N and it is parked with its center of gravity located 12.0 meters from the right pier. What upward support force must be provided by the left pier?

  159. algebra

    A town has a population of 8400 in 1990. Fifteen years later, its population grew to 12500. Determine the average annual growth rate of this town's population. How do i solve this using applications of exponential functions?

  160. Chemistry

    cyclopentanol ----> cyclopentanone Which of the following sets of reagents could be used to accomplish the above transformation? a)CrO3/H2SO4 b)KMnO4/H2O c)71% HNO3 @ 10-20 degrees Celcius d)all of the above

  161. Geometry - Bob

    Problem : Howm do you find the area of a circle circumscribed about a regular pentagon with a perimeter of 50 inches. So far I each side of pentagon is 10. How do I find the radius of the circle? Is this the correct direction to go? I your link & I was

  162. calculus

    a box has a length of 32 centimeters a width of 51 cm and a height of 19 cm. calculate the volume of the box.

  163. Algebra

    I am racking my brain trying to figure out how to work this: the square root of 55 minus the square root of one over 55 plus the square root of 5 over 11. Do I use conjugates? Ahhhh!

  164. math

    The top speed of a cheetah is 71 miles per hour. Which of the following answers seems most reasonable for the distance a cheetah would cover in 25 minutes at this speed?

  165. English

    This is a thank you letter to a company. Please check it and let me know what you think. If I need to change something or its just fine. Check for any errors. Thank you very much for taking the time to meet with me on April 14 regarding the position of

  166. Algebra

    An airline has implemented a plan to reduce the occurrence of lost luggage. They have observed a linear relationship between the number of months the plan has been in place and the number of pieces of lost luggage. The airline recorded their findings in

  167. Physics

    How do I find Period T(s) and Period^2 T^2 (s^2) given mass(kg) = 0.1 and Average time for ten vibrations (s) = 5.05?

  168. Chemistry

    Sodium ions when combined with chlorine irons produces sodium chloride

  169. english

    Is these all the adverbs and ajectives in this movie review? Raj, Yogi and Vikram - best friends, business partners, serial womanizers and happily married! Happy, because their lovely wives have no clue that their husbands cheat on them with every pretty

  170. Physical science

    How early did s.a incorporated the stars into their world explaing how they used stars to mark seasons and events events and retelling some legends and some stories linked with specific stars and constellations

  171. social studies

    What are the pros and cons of textbook social studies learning?

  172. Chemistry

    Sodium ions when combined with chlorine irons produces sodium chloride

  173. TX Goverment

    Does the state (Texas) system for raising revenue rely too much on regressive mechanisms like sales tax, user fees and licenses?

  174. physics

    A door, essentially a uniform rectangle of height 2.00 m, width 0.78 m, and weight 136.0 N, is supported at one edge by two hinges, one 18.1 cm above the bottom of the door and one 181.9 cm above the bottom of the door. Calculate the horizontal components

  175. physics

    A ladder of mass 39.0 kg and length 3.18 m is leaning against a wall at an angle θ. The coefficient of static friction between ladder and floor is 0.298; assume that the friction force between ladder and wall is zero. What is the maximum value that θ can

  176. Chemistry HELP!!

    What is the final energy level of an electron that absorbs energy of 656nm if the electron started at the n=2 level of the hydrogen atom?

  177. Algebra

    {1,3,5}¿

  178. College Algebra

    Staples recently charged $17.99 per box of Pilot Precise rollerball pens and $7.49 per box for Bic Matic Grip mechanical pencils. If Kelling Community College purchased 120 such boxes for a total of $1234.80, how many boxes of each type did they purchase?

  179. Doral Middle

    phillip has a 40-foot ladder that is placed 11 feet from a vertical wall. hw far above the ground will the top of the ladder be on the wall, in feet?

  180. Math HELP!!!

    HELP!!! I don't understand the question and need an asnwer fast! Two different memberships are available at a discount department store. The Type A membership costs $200 and allows you to enter the store and take 75% off the marked price. The Type B

  181. physics

    In preparation for a demonstration on conservation of energy, a professor attaches a 8.7-kg bowling ball to a 3.2-m-long rope. He pulls the ball 18° away from the vertical and holds the ball while he discusses the physics principles involved. Assume that

  182. Math

    Five balls are selected at random without replacement from an urn containing three white balls and five blue balls. Find the probability that two or three of the balls are white.

  183. Math

    Oranges are on sale at $0.99 per pound. Either bought 3.25 pounds of oranges. About how much did she pay for the oranges?

  184. calculus

    Please help. I need ( with details) how to differentiate with the chain rule f(x)=(x^2-6x+23)^3/2. I need to

  185. English

    Can you please check the following sentences? I included a short summary of Dr Jeckyll. Thank you. 1) The story was particulary appealing to the self-made and self-reliant tradesman. 2)Reference (or references were) was made to names of countries, streets

  186. hum186

    8. Explain the effect of relationships among TV, movies, and electronic games and culture.

  187. MATH

    One side of a rectangle is 53cm another, another side is 29 cm. What is the perimeter of the rectangle

  188. chemsitry

    buffer calculate the ph of the .1m propanoic acid Ka 1.35e-5

  189. AP US History

    Analyze the extent to which TWO of the following influenced the development of democracy between 1820 and 1840. -Jacksonian economic policy -changes in electoral politics -Second Great Awakening -Westward movement

  190. physics

    To the nearest order of magnitude, how many times greater than the speed of sound is the speed of light? 104 106 1010 1012

  191. Literature(Please help)

    I tryed finding information on how to cite a movie in MLA style but I am still confused. I need to cite the movie Smooth Talk by Joyce Chopra. All I know is the name of the movie, director, pg-13 and 1986. Please help. Thank you. Also, I need to cite a

  192. math

    A bag holds 8 yellow marbles and 5 orange marbles.How many and what color marbles would you add to the bag so that the probability of picking a yellow marble is 2/3

  193. history

    describe how greek philosophers were different from those that existed in other ancient civilizations. HELP!!!!!!!!!!!!!

  194. Physics

    A 7uF capacitor is charged to a potential difference of 110V The electrical energy stoed in the capacitor is (4.2x10^-2 was the given answer) but I used C=Q/V and keep getting 7.7x10^-4 also A particle of charge Q and mass m is accelerated from rest

  195. World Lit.

    How does the rulling government affect the daily lives of those in afghnistan? in a Thousand Slendid Suns

  196. science

    At which elevation would you be above one half of the mass of Earth's atmosphere?

  197. English

    I forgot to include this last sentence. 1) Prospero believes that Caliban should be grateful to him since he let him stay at his house and taught him to speak. In point of facts, Prospero says Caliban is a liar, who responds better to the whip than to

  198. Com 155

    Write five sentences about the role of education in successful financial planning, in which you correctly use a different verb tense in each sentence. Mark each verb used in bold and, in parentheses, identify the specific tense used. An education "could"

  199. chem

    A student weighs out a 13.7 g sample of Cr(NO3)3, transfers it to a 300 mL volumetric flask, adds enough water to dissolve it and then adds water to the 300 mL tic mark. What is the molarity of chromium(III) nitrate in the resulting solution?

  200. Chemistry

    Given that the Ka of benzoic acid is 6.50 x 10-5, how would one prepare 0.500 L of a benzoic acid/sodium benzoate buffer of a desired pH of 4.00? The starting concentration of the benzoic acid is 3.00 M and the molecular weight of sodium benzoate is 144.10

  201. World Lit.

    How do the characters of Laila and Mariam develop over time? in a Thousand Splendid Suns

  202. Chemistry

    What is the final energy level of an electron that absorbs energy of 656nm if the electron started at the n=2 level of the hydrogen atom?

  203. math

    What is the value for the numerals with letters. 245,189 a b c

  204. science

    How many gallons of fossil fuel to make a gallon of each of the following? synfuel soy ethanol cellulosic electricity

  205. World Lit.

    I am about to write an essay on How does the rulling government affect the daily lives of those in afghnistan? (in a Thousand Slendid Suns). what is a good thesis statement and a hook for this.

  206. MATH

    WHAT IS THE VALUE FOR THE NUMERALS WITH LETTERS 2 4 5, 1 8 9 a b c

  207. English

    I like my kimchi mild. (Does 'mild' modify kimchi? What is the opposite of 'mild'?)

  208. psychology, english

    how do you cite in APA style when there's more than one author is this correct (Smith, Young, 2002)?

  209. Models for Health and wellness

    Discribe one of the contemporary models of health from another country, and discribe its strengths and weaknessess.

  210. English

    He asked me a question. He asked a question of me. He begged me a question. He begged a question of me. He inquired me a question. He inquired me of a question. (Are the pairs all correct and interchangable? Doe they have the same meaning?)

  211. physics

    An object rests on the surface of planet y. Its mass is unknown. Find the acceleration due to gravity near the surface of planet y. Answer in m/s/s. G=6.673x10^-23 radius of planet y=2439700m mass of planet y=3.302x10^23kg radius of planet x=71492000m mass

  212. Math

    i will retype this question. What is the value for the numerals with letters. 2 4 5, 1 8 9 a.......b........9.....

  213. Topic on Florida

    My daughter is in fifth grade & she is required to do a five minute oral report on Oranges from Florida with props. Do you have any ideals?

  214. math

    Lets try this one last time What is the value for the numerals with letters: 245,189 2=a 5=b 8=c

  215. Math

    i have trouble factoring this equation any time x^2 has a number before it i get confused and don't know how to factor how would you solve this -3x^2+5x-2

  216. physics

    What is the heat of fusion of silver? what is the heat of vaporization for silver? what is the specific heat of silver? thank you.

  217. statistics

    For a population that has a standard deviation of 10, figure the standard deviation of the distribution of means for samples of size- (b) 3.

  218. geometry

    a cylinder that has a diameter of 2.5in. and length of 5.5ft, determine the volume of a) inches; b)feet

  219. accounting

    a merchandising company wants to include the cost of operating its warehouse in the cost of inventory. The company’s controller argues that the cost of the warehouse is a reasonable and necessary cost of getting the inventory ready for sale and,

  220. English

    1. He has finally paid his debt to society. (What does 'society' mean here? Did he pay the debt to a bank or just the society he lives in?)

  221. Geometry

    the width of a rectangle is 25% of the length. The perimeter is 250 cm. Find the width and the length of the rectangle. (length = 100 cm and width = 25cm)

  222. English

    His invention is superior to previous _______. (Can we put 'gift' in the blank? Which expressions are suitable for the blank? Would you name some of them? Can we use 'one'?)

  223. physics

    A swinging rope is used to transport 0.03kg of medicine. The rope has a length of 2.4m, so that the tension of the rope at the bottom point of the swing is 0.3929N. What is the tangential speed of the medicine at this bottom point? Answer in m/s. Thanks.

  224. English

    1. He is the top of the class. 2. He is at the top of the class. 3. He is the bottom of the class. 4. He is at the bottom of the class. (Is each pair interchangable and grammatical? Is #1 or #2 opposite of #3 or #4?)

  225. Calculus (please help!!!!)

    Consider a window the shape of which is a rectangle of height h surmounted a triangle having a height T that is 1.3 times the width w of the rectangle. If the cross-sectional area is A, determine the dimensions of the window which minimize the perimeter.

  226. English

    1. The nurse mixed him a bottle of medicine. 2. The nurse made him a bottle of medicine. 3. The nurse made him a mix/mixture of medicine. (Which ones are grammatical? Is #1 a correct sentence?)

  227. english

    pls what is the theme in the novel honey, baby , sweetheart. how is this story a tragic story

  228. math

    Solve 1/2x - 7 = 21

  229. Chem

    The total pressure in an 11.1L automobile tire is 40psi at 13 degree celcius. By how much does the pressure in the tire rise if it warms to a temperature of 56 degrees celcius and the volume remains at 11.1L ?

  230. physics

    A trapdoor on a stage has a mass of 20.8 kg and a width of 1.51 m (hinge side to handle side). The door can be treated as having uniform thickness and density. A small handle on the door is 1.41 m away from the hinge side. A rope is tied to the handle and

  231. physics

    A rigid rod of mass m3is pivoted at point A, and masses m1 and m2 are hanging from it, as shown in the figure. (a) What is the normal force acting on the pivot point? The ratio of the weights of m1, m2, and m3 is 1:2:3. (Use the following as necessary: m1

  232. physics

    George has a large circular table with a circumference of 18 feet.what is the approximate area of the table?

  233. Mass Media

    What are the various information delivery methods to audiences?

  234. physics

    the density of gold is 19.3 x 10^3, what buoyant force does a .60-kg gold crown experience when it is immersed in water?

  235. math

    simplify: 1. a^2b^-3 2. (5/3)^-3 3. (a^2b^0c)^0 4. x^-2y^3 5. 3x^-2 6. n^2/n^-3 please help!!

  236. trig

    2cos(theda)-"2=0

  237. Physics

    A resitor of unknown resistance and a 35-omega resistor are connected across a 120-V emf device in such a way that an 11-A current flows. What is the value of the unknown reisistance?

  238. English

    1. Teacher shake me by the shoulder when I am sleeping in class. 2. The teacher shakes me by the shoulder when I am sleeping in the class. (Is #1 right? What about #2? Do we have to use 'in class' or 'in the class'?)

  239. English

    Thank you for your corrections. I really need to know if the following sentences are possible. 1) Before Jack White formed the White Stripes he had played the guitar in a group called Go. 2) He and his wife Meg developed a distinctive style. They wore only

  240. English

    What does the word "curfew" mean in this sentence: "A game well played, but curfew is past!"

  241. psy 220

    HELP going through home CRISIS Find a peer reviewed article which discusses the effects of optimism on physical and psychological health. (You may need to find two articles in order to cover both the physical and the psychological areas).

  242. Math

    In a triangle, one angle is twice the measure of the second angle. The third angle is three times the measure of the second angle. Find the measure of eah angle.

  243. Chemistry

    What is the maximum mass of the lower molar mass product that can be formed when 71.0 g of solid barium bromide and 44.5 g chlorine gas react?

  244. math

    In an Isosceles triangle, one angle is 16 degrees more than twice the measure of one of the equal angles. Find the measure od eah angle.

  245. question

    Thank you for your help. I can learn a lot of useful and corect English expressions here. By the way, when I search what I have uploaded, I can not find the recent questions first, which is different from before.

  246. English

    Will write a paragraph of what they think is the best defense mechanism of the Bess beetle and why. Is this sentece correct or should Bess be lower case?

  247. science

    How do I build a 10cm by 8 cm (width) cardboard chair, with 4 legs, two arms, that holds 4 soup cans for 2 minutes?