Popular questions and responses by jane
  1. physics

    The energy given off by 300 grams of an alloy as it cools through 50°C raises the temperature of 300 grams of water from 30°C to 40°C. The specific heat of the alloy (in cal/g C ) is: i know Q=CpM(delta T) but what is what?

    asked on June 22, 2009
  2. Statistics

    The lengths of pregnancies are normally distributed with a mean of 273 days and a standard deviation of 20 days. If 64 women are randomly selected, find the probability that they have a mean pregnancy between 273 days and 275 days.

    asked on February 10, 2013
  3. Physics

    A current of 60 mA passes through a loudspeaker of resistance 6 Ω. What is the potential difference across the resistance of the loudspeaker? 36.0 V 10.0 V 0.36 V 0.10 V Answer B seems like it would be the obvious answer..

    asked on October 22, 2012
  4. chemistry

    One step in the isolation of pure rhodium metal (Rh) is the precipitation of rhodium(III) hydroxide from a solution containing rhodium(III) sulfate According to the following balanced chemical equation: Rh2(SO4)3(aq)+ 6NaOH(aq)→ 2Rh(OH)3(s)+ 3Na2SO4(aq)

    asked on March 14, 2013
  5. Chemistry

    If 1.50 g of H2C2O4 2H2O were heated to drive off the water of hydration, how much anhydrous H2C2O4 would remain? Thank you! Please explain clearly.

    asked on December 19, 2013
  6. physics

    At a picnic, there is a contest in which hoses are used to shoot water at a beach ball from three directions. As a result, three forces act on the ball, F1, F2, and F3 (see drawing). The magitudes of 1 and 2 are F1 = 55.0 newtons and F2 = 95.0 newtons.

    asked on September 12, 2010
  7. physics

    what pressure (in atm) would be exerted by 76g of fluorine gas in a 1.5 litre vessel at -37 degrees Celsius?

    asked on April 26, 2013
  8. Math

    There are 12 more toy cars than toy trucks in a toy box with a total of 38 toy cars and trucks. How many toy trucks are in the toy box?

    asked on July 5, 2016
  9. Math

    Peter has 1200 yards of fencing to enclose a rectangular area. Find the dimensions of the rectangle that maximize the enclosed area?

    asked on December 4, 2012
  10. physics

    To what temperature must you raise a copper wire, originally at 20.0°C, to double its resistance, neglecting any changes in dimensions? (Does this happen in household wiring under ordinary circumstances?)

    asked on September 13, 2014
  11. Chemistry

    For the cell diagram Pt(s)|H2(g)|H+(aq)||Cu2+(aq)|Cu(s) Write a balanced equation for the half-reaction at the cathode. The cathode is the site of reduction so copper gets reduced. So wouldn't the answer be: Cu2+(aq) -> Cu(s) + 2e-?

    asked on June 11, 2013
  12. Maths

    Andrew arranged the number 1, 2, 3, ...11, 12 into six pairs so that the sum ofany two numbers in a pair is prime and no two of these primes are equal. find the primes and the pairs

    asked on February 3, 2010
  13. physics

    A 0.400 kg ball is shot directly upward at initial speed 40.0 m/s. What is its angular momentum about a point 2.0 m horizontal from the launch point, when the ball is a) at maximum height and b) halfway back to the ground? What is the torque on the ball

    asked on June 13, 2009
  14. Math

    Two ships leave the same port at the same time. One ship sails on a course of 110 degree at 32 mi/h. The other sails on a course of 230 degree at 40 mi/h. Find the distance between them after 2 hours. Express your answer to the nearest mile.

    asked on March 5, 2018
  15. trig

    ABC is rightangled triangle. AD is the bisector of angle BAC. Angle DAC=15 degrees. X=CD. Find X. I know the answer is 7.1 but do not know how to do the actual sum. Can you please help AB = 23 CM

    asked on May 5, 2011
  16. Math

    Translate the sentence into an inequality. Ten times the sum of a number and 27 is at least 26.

    asked on October 1, 2017
  17. math

    a garden 7m by 12m will be expanded by planting a border of flowers,the border will be of the same width around the entire garden and has an area of 92m

    asked on June 18, 2016
  18. math

    Find p such that px^2-12x+4=0 has only one solution. Thank you!!!

    asked on April 14, 2016
  19. math

    A local citizen wants to fence a rectangular community garden. The length of the garden should be at least 110 ft, and the distance around should be no more than 380 ft. Write a system of inequalities that models the possible dimensions of the garden.

    asked on December 29, 2011
  20. History/ Civics

    1.How did the capture of Vicksburg, Mississippi, take advantage of a Confederate weakness? A-The Confederacy had few soldiers and relied on its well-trained generals to win battles. B- The Confederacy had few weapons manufacturers and relied on Vicksburg

    asked on April 29, 2015
  21. chemistry

    i already posted this question, but im still confused on it. Dinitrogentetraoxide partially decomposes according to the following equilibrium: N2O4 (g) -> 2NO2 (g) 2NO2 (g) Initial conc. 0.400 mol 0 mole (no reaction yet) Change -0.3945 mol + 2 x 0.3945

    asked on October 26, 2010

    paid two months rent deposit and one month advance, P40,500

    asked on August 23, 2014
  23. math

    A cyclist travels for 60km at x km/h and 180km at y km/h and takes 10 hours altogether for the journey. If the speed are interchange, the journey takes 8.6 (8 whole number 2 over 3) hours. Find x and y.

    asked on November 16, 2015
  24. Physics

    A circular plate of radius 0.5 m is placed perpendicular to the direction of the magnetic field of 0.5 Tesla. What is the change of flux in the plate if it rotates and its plane becomes parallel to the direction of the magnetic field?

    asked on May 17, 2013
  25. Geometry

    Please explain how to work this problem: A pair of earrings has blue wedges that are all the same size. One earring has a 25 degree yellow wedge. The other has a 14 degree yellow wedge. Find the angle measure of a blue wedge. How do the angle measures of

    asked on September 13, 2012
  26. chemistry

    suppose 250 mL of a .433 M solution of CuCl2 is electrolyzed. how long will a current of 75A have to run in order to reduce the concentration of Cu2+ to .167M? What mass of Cu will be deposited on the cathode during this time?

    asked on June 18, 2012
  27. arithmetic

    The initial term of an arithmetic sequence is 5. The eleventh term is 125. what is the common difference of the arithmetic sequence?

    asked on October 25, 2011
  28. Math

    A surveyor sights two signs and the angle between the two lines of sight measures 55. If the first and the second signs are 70 m and 50 m away,respectively,from the surveyor, find the distance between the two signs .Express your answer to the nearest

    asked on March 5, 2018
  29. chemistry

    A certain first order reaction has a rate constant of 5.68 x 10–3 s–1 at 139°C and a rate constant of 8.99 x 10–1 s–1 at a temperature of 215°C. Ea = 111 kJ mol– q1) What is the value of the rate constant at 275°C? q2) At what temperature does

    asked on June 2, 2016
  30. Math please help quick

    Which of the following are identities? Check all that apply. (Points : 2) sin2x = 1 - cos2x sin2x - cos2x = 1 tan2x = 1 + sec2x cot2x = csc2x - 1 Question 4. 4. Which of the following equations are identities? Check all that apply. (Points : 2) Question 5.

    asked on January 12, 2014
  31. Chemistry Class

    Dinitrogentetraoxide partially decomposes according to the following equilibrium: N2O4 (g) -> 2NO2 (g)

    asked on October 25, 2010
  32. biology

    Which of the following organs remove nitrogenous waste from the body? a. Liver b. Large Intestine c. Kidneys d. Gall Bladder

    asked on January 26, 2017
  33. Chemistry

    Please help! Calculate the standard change in enthalpy, ΔH°rxn, for the decomposition of calcium carbonate to calcium oxide CaCO3 (s) → CaO (s) + CO2 (g) Given that: ΔH°f CaCO3 (s) = -1206.9 kJ/mol ΔH°f CaO (s) = -635.1 kJ/mol ΔH°f CO2 (g) =

    asked on September 27, 2014
  34. 8need a function rh grade math

    a 154 lb person burns 420 calories per hr riding an exercise bike at 15 mph. Need a function rule to represent the total calories burned over time.

    asked on May 14, 2013
  35. Alg 1

    Diana is driving 182 miles to Orlando for a math convention. She has already driven x miles of th trip. If Diana drives below 70 miles per hour for the remainder of th trip, which inequality best represents the amount of time in hours, t, that is will take

    asked on April 29, 2013
  36. alg 1

    Find the percent error in calculating the volume of the prism. V=(bw)(h) v=11 x 8 (7) V=616 my choices were: 19% 10% 119% 83% I'm not sure what it means to find the percent error. Please explain. Thanks.

    asked on April 16, 2013
  37. Alg 1

    A golden rectangle is 32 cm long. The ratio of length to width is (1 + sq rt 5)/2. What is the width of the rectangle in simplest radical form? Please solve and explain. Thanks.

    asked on April 3, 2013
  38. Trigonometry- Application of Sine and Cosine Law

    Q: A 4m flag pole is not standing up straight. There is a wire attached to the top of the pole and anchored in the ground. The wire is 4.17m long. The wire makes a 68 degree angle with the ground. What angle does the flag pole make with the wire? Show all

    asked on February 12, 2019
  39. Please help me with Trig

    Given cos 67.5° = [√(2+√2)]/2, find tan 67.5° , simplify where needed, and show work. I'm starting to learn this stuff, and I'm so confused where to start. I know they gave me the coordinate X as in cos 67.5° = [√(2+√2)]/2, and I also know that

    asked on January 27, 2016
  40. Math

    A golfer stands 420ft(140 yd) horizontally from the hole and 50ft above the hole. Assuming the ball is hit with an initial speed of 120ft/s, at what angle should it be hit to land in the hole? Assume the path of the ball lies in a plane.

    asked on March 6, 2014
  41. physics

    A truck is pulling a car. FT is the magnitude of the force that the truck exerts on the car FC is the magnitude of the force that the car exerts on the truck Consider the following scenarios independently. 1)The truck is driving with a constant velocity,

    asked on February 13, 2014
  42. chemistry

    4NH3 + 5O2 → 4NO + 6H2O 2NO + O2 → 2NO2 3NO2 + H2O → 2HNO3 + NO In this process, the NO made in the last reaction is recycled back into the second reaction and used as a reactant. In the end, all of the NO produced is recycled back so that when the

    asked on September 29, 2011
  43. Math

    Given a geometric progression whose common ratio is 2, if the sum of the 6th to 7th terms is 288, determine the sum of the 4th to 15th terms inclusive.

    asked on April 18, 2020
  44. Algebra

    Classrooms on one side of the drama building are all numbered with consecutive even integers. If the first room, the room with the smallest classroom number, on this side of the building is numbered x, write an expression in x for the sum of the first five

    asked on September 1, 2017
  45. Alg 1

    Simplifying Radicals A gardener is mowing a 20-yd-by-40 yd rectangular pasture using a diagonal pattern. He mows from one corner of the pasture to the cxorner diagonally opposite. What is the length of this pass with the mower? Give your answer in

    asked on April 2, 2013
  46. Physics

    A balloon carrying a basket is descendign with a constant acceleration of g/3. the total mass of the basket and contents is mB.you see water below and decide you need to throuw out some mass to allow the basket to rise and not hit the water. how much mass

    asked on October 8, 2012
  47. math

    Please show me how to solve: At the local ballpark, the team charges $5 for each ticket and expects to make $1,300 in concessions. The team must pay its players $1,800 and pay all other workers $1,500. Each fan gets a free bat that costs the team $3 per

    asked on December 29, 2011
  48. Chemistry

    The following isotopes (listed with their half-lives) have been used in the medical and biological sciences. Arrange these isotopes greatest to least decay activity. (Use the appropriate symbol to separate substances in the list.) ^3H (12.2 years) ^24Na

    asked on November 27, 2010
  49. physics

    if some of water in calorimeter splash out when tranfering the metal block, will it affect the experiment result?

    asked on May 22, 2017
  50. Physics

    two blocks (a and b) are in contact on a horizontal frictionless surface. a 60N constant horizontal force is applied to A. the mass of a is 3.0 kg and the mass of b is 15 kg. what is the magnitude of the force of a on b

    asked on October 27, 2016
  51. Math

    Pythagorean Theorem A rectanglar box is 9 in. wide, 11 in. tall, and 20 in. long. What is the diameter of the smallest circular opening through which the box will fit? If necessary, round to the nearest tenth of a centimeter.

    asked on April 1, 2013
  52. geometry

    Algebra BD bisects

    asked on September 14, 2012
  53. medicinal chemistry

    the solubility product of PbSO4 at 298K is 1.6x10^-8 mol^2dm^-6. Calculate the solubility of PbSO4 in 0.10mol dm^-3 sulphuric acid.Thanks!

    asked on May 28, 2012
  54. Math

    A copy center offers its customers two different pricing plans for black and white photocopies of 8.5 in. by 11 in. pages. Customers can either pay $0.08 per page or pay $7.50 for a discount card that lowers the cost to $0.05 per page. Which equation can

    asked on January 5, 2012
  55. Data management

    1)SOLVE: a) 2nP3 = 2(nP4) b)6(n+1P2) = 3nP2 2) If (nC12 = (nC8), find (nC17) and (22Cn) 3)simplify. a) n(squared) (n-2)! - n(n-2)! / n! b) (nC2) - (nCn-2) 4)If nPr - 506 and (nCr_ = 253, find n and r. 5) If (28C2r)/(24C2r-4) = 225/11, find r.

    asked on October 27, 2011
  56. Math

    3/5 of the booksin a class library are englishbooks. The rest are non-english books. If the total number of books in the library is 650, how many non-english books are there?

    asked on September 30, 2018
  57. maths

    i have two piece of ribbon one is 17.5cm longer than the other and 1/3 of one ribbon is the same as 3/4 of the other what is the size of the smaller ribbon

    asked on July 9, 2017
  58. statistics

    Of the 6796 students in one school district, 1537 cannot read up to grade level. Among a sample of 812 of the students from this school district, 211 cannot read up to grade level. Find the sample proportion of students who cannot read up to grade level.

    asked on April 17, 2015
  59. math

    The amount of Jen’s monthly phone bill is normally distributed with a mean of $50 and a standard deviation of $10. Find the 25th percentile. A. About $46.30 B. About $43.30 C. About $43.40 D. about $43.20 I came up with $43.26 which its not a choice.

    asked on April 16, 2015
  60. physics

    An arrow is aimed horizontally, directly at a target 20.6 meters away. when the arrow is released, it lands 0.095 meters below the target point. a) How long was the arrow in the air? b) How fast was the arrow moving when it left the bow?

    asked on October 3, 2014
  61. Math

    If A= and B=, find the magnitude and direction angle for -2A +3B Find all specified roots: Cube roots of 8i A parallelogram has sides of length 32.7cm and 20.2cm. If the longer diagonal has a length of 35.1cm, what is the angle opposite this diagonal?

    asked on July 30, 2014
  62. Algebra

    The difference between the digits in a two-digit numeral is 3. The units' digit is twice the tens' digit. Find the nuermal.

    asked on October 22, 2012
  63. Chemistry

    Arrange the ions: Cu^2+, Ni^2+, Mg^2+, & Zn^2+ in order of decreasing ability to be reduced... & in order of decreasing ability to be oxidized

    asked on May 20, 2012
  64. Math

    The table shows the height of an elevator above ground level after a certain amount of time. Let y stand for the height of the elevator in feet and let x stand for the time in seconds. Which equation models the data below? Time (s) Height (ft) 10 235 20

    asked on January 5, 2012
  65. physics

    Find the length of a pendulum that has a frequency of 0.80 Hz?

    asked on November 24, 2010
  66. math

    You have $47 to spend on music and movie downloads. Each album download costs $7 and each movie download costs $8. Write and graph a linear inequality that represents this situation. Let x represent the number of albums and y the number of movies.

    asked on December 31, 2011
  67. calculus

    Find the exact value of: cos(arctan(2) + arctan(3)) Please explain how you got your answer. I have the answer, but I don't know how to get to it.

    asked on February 21, 2009
  68. last calc question, i promise!

    given the curve x + xy + 2y^2 = 6... a. find an expression for the slope of the curve. i got (-1-y)/(x + 4y) as my answer. b. write an equation for the line tangent to the curve at the point (2,1). i got y = (-1/3)x + (5/3). but i didn't any answer for c!

    asked on February 20, 2009
  69. Statistics

    Consider the probability that fewer than 17 out of 145 people will get the flu this winter. Assume the probability that a given person will get he flu this winter is 11%. Approximate the probability using the normal distribution. Round the answer to four

    asked on December 3, 2017
  70. calculus review please help!!

    The velocity of a particle moving along the x-axis is v(t) = t^2 + 2t + 1, with t measured in minutes and v(t) measured in feet per minute. To the nearest foot find the total distance traveled by the particle from t = 0 to t = 2 minutes.

    asked on April 27, 2017
  71. cal

    The demand function for a certain make of replacement cartridges for a water purifier is given by the following equation where p is the unit price in dollars and x is the quantity demanded each week, measured in units of a thousand. p = -0.01x^2 - 0.3x +

    asked on December 2, 2014
  72. Chemistry

    A 10.0 gram sample of a mixture of CH4 and C2H4 reacts with oxygen at 25°C and 1 atm to product carbon dioxide gas and liquid water. If the reaction produces 520 kJ of heat, what is the mass percentage of CH4 in the mixture? I am all out of tries on the

    asked on October 27, 2014
  73. English Imperative Sentences

    Can someone please check my answers? *Cross out any prepositional phrases. Underline the subject once and the verb/verb phrase twice. 1. Give this tip to the waiter in the checkered shirt. (subject- you verb- give prepositional phrase- to the waiter, in

    asked on October 27, 2013
  74. Alg 1

    Completing the square: Which of the following is a solution x^2 + 14x + 112 = 0? If necessary round to the nearest hundredth. x= -0.24 x= -4.24 x= 4.24 no solution I worked it and got neither of the answers. I got x= 0.9 and x=-14.9. Where did I go wrong?

    asked on April 14, 2013
  75. math

    A rectanglar blacktop with a length of 5x and a width of 3x has been erected inside a rectangular field that has a length of 12x and a width of 7x. What is the area of the part of the field that is not blacktop? (I believe the answer is 69x^2) There is a

    asked on March 1, 2013
  76. physics

    An airplane flies 200km due west from city A to city B and then 305km in the direction of 33.5 degrees north of west from city B to city C. a.) in straight-line distance, how far is city C from city A? b.) relative to city A,in what direction is city C?

    asked on January 28, 2013
  77. math

    How do I set this up and solve? You are planning a rectangular patio with length that is 7 ft less than 3 times its width. The area of the patio is 120 ft squared. What are the dimensions of the patio?

    asked on February 27, 2012
  78. Math

    Which equation is not equivalent to A = 1/2bh 2A=bh h=2A/b 2b=A/h b=2A/h I think it is 2b=A/h. Is this correct?

    asked on January 7, 2012
  79. math

    Please explain how to solve: Reid and Maria both play soccer. This season, Reid scored 4 less than twice the number of goals that Maria scored. The difference in the number of goals they scored was 6. How many goals did each of them score?

    asked on December 31, 2011
  80. Intro to calc

    3 numbers x y and z are to bea randomly chosen between 0 and 1. A What is the probability that X + y + z will be less than 1? B What is the probability that both x+ y

    asked on July 20, 2011
  81. macroeconomic theory

    4. If an individual's utility function for coffee (x) and cream (y) is given by U(x, y) = min (x, 5y), write the demand function for coffee .

    asked on December 10, 2010
  82. math/probability

    find the number of possible choices when you choose one item from each category. 1. 3 hats, 7 shirts, 13 scarves 2. 6 pens, 2 nbk 3. 4 cars, 2 colors i don't get the question

    asked on April 8, 2010
  83. Chemistry

    An aqueous solution of glucose (C6H12O6), called D5W, is used for intravenous injection. D5W contains 54.30 g of glucose per liter of solution. What is the molar concentration of glucose in D5W?

    asked on June 11, 2020
  84. Chemistry

    How many moles of Mg2+ and NO3− form for each mole of Mg(NO3)2 that dissolves?

    asked on June 11, 2020
  85. chemistry

    The active ingredient in some antiperspirants is aluminum chlorohydrate, Al2(OH)5Cl. Analysis of a 2.000-g sample of antiperspirant yields 0.334 g of aluminum. What percent (by mass) of aluminum chlorohydrate is present in the antiperspirant? (Assume that

    asked on December 19, 2018
  86. Math

    Paul is 20 years older than joy four years ago; the ratio of their ages was 7:3 find the present age of Paul

    asked on May 20, 2018
  87. Calculus

    A rectangle is bounded by the x-axis and the semicircle y = sqrt(36-x^2). What length and width should the rectangle have so that its area is a maximum? I understand that 2xy = A and that 4x + 2y = P, but I'm not sure how to solve for a variable to plug

    asked on March 2, 2016
  88. math

    The batting averages of the first three batters in the Eureka College women’s softball team lineup are .310, .301, and .277. If the first three batters are considered as the “lead-off group”, what is the batting average of the group? A. .301 B. .296

    asked on April 15, 2015
  89. Science

    I answered the questions, but I don't know if my choices are right. 1) Which of the following is an acidic pH? 6 7 8 800 None of the Above Answer: 6 ------------------------------------- 2) Which of the following is directly produced by photosynthesis?

    asked on March 21, 2015
  90. Chemistry

    Consider the following reaction, equilibrium concentrations, and equilibrium constant at a particular temperature. Determine the equilibrium concentration of H2O(g). C2H4(g) + H2O(g) C2H5OH(g) Kc = 9.0 × 103 [C2H4]eq = 0.015 M [C2H5OH]eq = 1.69 M

    asked on December 2, 2014
  91. Algebra 2

    Can someone please explain how to do this problem? A 450 foot tall building is near a shorter building. A person on top of the shorter building finds the angle of elevation of the roof of the taller building to be 25 degrees and the angle of depression of

    asked on April 30, 2014
  92. Alg 1

    The product of two consecutive integers, n and n+1, is 42. What is the positive integer that satisfies the situation? Is it 6 x 7?

    asked on April 13, 2013
  93. math

    There were 20% more boys than girls in a swimming club. After 50 girls left, there were twice as many boys as girls in the club. How many boys were there in the club?

    asked on November 30, 2012
  94. math

    Which value below is a possible solution to the compound inequality 0

    asked on April 12, 2012
  95. math

    Simplify the radical expression by rationalizing the denominator: 2(square root)108 / (square root) 180y Please show me how to set up and how to solve

    asked on March 21, 2012
  96. Math

    Please show me how to set it up and to solve: A cell phone company sells about 500 phones each week when it charges $75 per phone. It sells about 20 more phones per week for each $1 decrease in price. The company's revenue is the product of the number of

    asked on February 11, 2012
  97. Chemistry

    Write the molecular equation, the complete ionic equation, and the net ionic equation for the reaction of barium hydroxide with sodium nitrate.

    asked on November 23, 2011
  98. math

    a function is (always, never or sometimes) a relation.

    asked on October 27, 2011
  99. College Physics

    6. A tall bald student (height 2.1 meters and mass 93.1 kg) decides to try bungee jumping from a bridge. The bridge is 36.7 meters above the river and the "bungee" is 25.3 meters long as measured from the attachment of the bridge to the foot of the jumper.

    asked on June 29, 2011
  100. chemistry

    what is the reagent responsible for the formation of hydrogen sulfide?

    asked on May 4, 2011


  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6
  7. 7
  8. 8
  9. 9
  10. 10
  11. 11
  12. 12
  13. 13
  14. 14