Most popular questions and responses by John
  1. Calculus

    A stone is dropped from the upper observation deck of a tower, 200 m above the ground. (Assume g = 9.8 m/s^2.) a)Find the distance (in meters) of the stone above ground level at time t. b)With what velocity does it strike the ground? (Round your answer to

    asked on November 13, 2011
  2. science

    Both carbon dioxide and water are pure substances. How are they similar to each other? A. both substances have a set ratio of atoms that cannot be separated by physical means B. both substances have a set ratio of atoms that can be separated by physical

    asked on October 8, 2015
  3. English

    1. Early in Act II of The Phantom Tollbooth, Milo meets a character named Kakafonous A. Dischord, Doctor of Dissonance. Stage directions tell you that "Two screeches and a bump are heard." The doctor's name and the stage directions are clues to the

    asked on December 3, 2018
  4. english

    21. identify the appropriate punctuation for the underlined word or phrase In High School, I enjoyed reading (The Catcher in the Rye)

    asked on October 25, 2016
  5. algebra

    Cryptic Quiz 1. What do you call a skydiver with the flu? 2. How do you crash a houseboat party?

    asked on May 2, 2013
  6. math

    Pizzaz pg.103 Did you hear about...

    asked on January 8, 2012
  7. Physics

    Question: A Toyota car travelled at the rate of 70 km/hour leaves the house 2 hours after a Kia car has left and overtakes it in 5 hours. at what rate was Kia car travelling? What's the Formula pls? Thanks

    asked on July 21, 2016
  8. Statistics

    you roll two fair dice, a green one and a red one? (a) are the outcomes on the dice independent? (b)Find P(1 on green die and 2 on red die) (c)Find P(2 on green die and 1 on red die) (d)Find P(1 on green die and 2 on red die) or (2 on green die and 1 on

    asked on October 30, 2016
  9. Chemistry

    Tarnish on iron is the compound FeO. A tarnished iron plate is placed in an aluminum pan of boiling water. When enough salt is added so that the solution conducts electricity, the tarnish disappears. Imagine that the two halves of this redox reaction were

    asked on May 14, 2014
  10. Wave

    What feature is NOT defined for a wave pulse? a)period b)wave speed c)the position of a particle at a certain time d)a defined source

    asked on February 8, 2014
  11. calculus

    If an arrow is shot upward on Mars with a speed of 52 m/s, its height in meters t seconds later is given by y = 52t − 1.86t2. (Round your answers to two decimal places.) What is the average speed over the given time intervals? (i) [1, 2] (ii) [1, 1.5]

    asked on January 31, 2018
  12. Physics

    Our sun rotates in a circular orbit about the center of the Milky Way galaxy. The radius of the orbit is 2.2 1020 m, and the angular speed of the sun is 1.2 10-15 rad/s. (a) What is the tangential speed of the sun? m/s (b) How long (in years) does it take

    asked on March 6, 2008
  13. Science

    How do global positioning systems use elevation points on Earths system to find latitude and longitude A. By using signals from a network of satellite B. By using topographic maps C. By using satellite images D. By using photography

    asked on May 19, 2017
  14. english

    25. which sentence is punctuated correctly? a. "Are you finished yet, Miriam asked?" b. Are you finished yet, " Miriam asked?" c. "Are you finished yet"?Miriam asked. d. "Are you finished yet?" Miriam asked.*** 26. Which sentence correctly uses punctuation

    asked on October 27, 2016
  15. science

    A chair of mass 15.5 is sitting on the horizontal floor; the floor is not frictionless. You push on the chair with a force = 38.0 that is directed at an angle of 42.0 below the horizontal and the chair slides along the floor.Use Newton's laws to calculate

    asked on August 3, 2012
  16. Physics

    In uniform circular motion, which of the following quantities are constant: speed, instantaneous velocity, tangential velocity, radial acceleration, tangential acceleration? Which of these quantities are zero throughout the motion?

    asked on October 8, 2013
  17. math

    Cyndee wants to invest $50,000. Her financial planner advises her to invest in three types of accounts: one paying 3%, one paying 5 1/2%, and one paying 6% simple interest per year. Cyndee wants to put twice as much in the lowest-yielding, least-risky

    asked on April 27, 2016
  18. math

    A hacker is trying to guess someone's password. The hacker knows (somehow) that the password is 14 characters long, and that each character is either a lowercase letter, (a, b, c, etc), an uppercase letter (A, B, C, etc) or a numerical digit (0, 1, 2, 3,

    asked on November 8, 2015
  19. physics vectors

    Consider the two vectors A with arrow = 3 i − j and B with arrow = − i − 6 j. Calculate the directions of A with arrow + B with arrow and A with arrow − B with arrow. A with arrow + B with arrow ° (counterclockwise from the +x axis) A with arrow

    asked on August 23, 2016
  20. Calculus

    For a cylinder with a surface area of 90, what is the maximum volume that it can have? Round your answer to the nearest 4 decimal places. The volume of a cylinder is πr^2*h and the surface area is 2πrh+2πr^2.

    asked on November 4, 2015
  21. English

    A: Hello. May I speak to Tom? B: Speaking. Who's calling, please? A: Hi, Tom. This is Sam. How are you doing? B: Just fine. How's your new school? A: It's great. By the way, what are you doing? B: I'm playing computer games. A: Will you come to Yunsan

    asked on April 20, 2009
  22. math

    In a family with 4 children what is the probability of having 1 boy and then 3 girls, in that order? (Exclude multiple births and assume all outcomes are equally likely). In a family with 4 children, what is the probability of having 1 boy and 3 girls, in

    asked on November 8, 2015
  23. Business Math

    Lisa Richter deposited $5,000 at 4% compounded semiannually for three years. At the beginning of the fourth year, Lisa deposited $2,500. What would her balance be at the end of five years assuming she is still earning 4% compounded semiannually?

    asked on April 24, 2016
  24. Pre-Calc Helppp!!!

    Use the Law of Sines to solve for all possible triangles that satisfy the given conditions. (If an answer does not exist, enter DNE. Round your answers to one decimal place. Below, enter your answers so that B1 is smaller than B2.) a = 39, c = 40, angle A

    asked on March 31, 2012
  25. physics

    Two cars leave the same point at the same time, each travelling at the same constant speed and each having the same mass. The first car drives directly east, while the second car heads directly north. If the centre of mass of the two-car system is

    asked on November 8, 2011
  26. Statistics

    One event A is _________________ of another event B if the probabilty of event A has occurred given event B is the same as the probability that A will occur with no knowledge of B. disjoint mutually exclusive dependent independent

    asked on November 15, 2012
  27. Chemistry

    Ni2+(aq)+Mg(s)→Ni(s)+Mg2+(aq) Indicate the half-reaction occurring at Anode. Indicate the half-reaction occurring at Cathode.

    asked on May 14, 2014
  28. math

    Jane is organizing a fundraiser to buy a ping-pong table for the community center. The table costs $500.00. Jane is asking contributors to pay for an equal share of the cost of the table. She already has five contributors lined up. What function models the

    asked on February 7, 2019
  29. Data Management

    How many different sums of money can be formed from one $2 bill, three $5 bills, two $10 bills, and one $20 bill? the answer at the back of the book is 23, but i don't know how to solve it.

    asked on March 6, 2010
  30. college physics

    Superman must stop a 190-km/h train in 180m to keep it from hitting a stalled car on the tracks. part a)If the train's mass is 3.8×10^5kg , how much force must he exert (find the magnitude)? part b)Compare to the weight of the train (give as %). partc)

    asked on April 29, 2012
  31. Calculus

    Sorry this is really long. Just wondering how I would do each of these A particle is moving with velocity v(t) = t^2 – 9t + 18 with distance, s measured in meters, left or right of zero, and t measured in seconds, with t between 0 and 8 seconds

    asked on February 14, 2016
  32. Chemistry

    If a copper sample containing some zinc impurity is to be purified by electrolysis, the anode and the cathode must be which of the following? a. anode: pure copper cathode: pure zinc b. anode: pure zinc cathode: pure copper c. anode: pure copper cathode:

    asked on April 14, 2008
  33. Econ

    Suppose the government wants to reduce the total pollution emitted by three firms in its area. Currently, each firm is creating 4 units of pollution in the area, for a total of 12 pollution units. The government wants to reduce total pollution in the area

    asked on May 19, 2012
  34. Chemistry

    Which of the following metals or nonmetals are expected to displace Mn or Cl (respectively) from MnCl2? 1. Ca should displace Mn. 2. Br should displace Cl. 3. Cu should displace Mn. 4. I should displace Cl.

    asked on September 22, 2013
  35. Calculus

    Which of the following integrals correctly computes the volume formed when the region bounded by the curves x^2 + y^2 = 100, x = 6, and y = 0 is rotated around the y-axis? I've narrowed it down to either pi∫(sqrt(100-y^2)-6)^2 dy or

    asked on January 22, 2016
  36. math

    Points $D$, $E$, and $F$ are the midpoints of sides $\overline{BC}$, $\overline{CA}$, and $\overline{AB}$, respectively, of $\triangle ABC$. Points $X$, $Y$, and $Z$ are the midpoints of $\overline{EF}$, $\overline{FD}$, and $\overline{DE}$, respectively.

    asked on March 3, 2015
  37. Science

    Do global positioning systems use elevation on Earths system to find latitude and longitude A. By using signals from a network of satellite B. By using topographic maps C. By using satellite images D. By using photography

    asked on May 19, 2017
  38. physics

    Two charges that are 2 meters apart repel each other with a force of 2 x 10-5 newton. If the distance between the charges is decreased to 1 meter, the force of repulsion will be A) 1 x 10-5 N B) 4 x 10-5 N C) 8 x 10-5 N D) 5 x 10-6 N

    asked on March 4, 2011
  39. Pre-Calc

    A hot-air balloon is floating above a straight road. To estimate their height above the ground, the balloonists simultaneously measure the angle of depression to two consecutive mileposts on the road on the same side of the balloon. The angles of

    asked on March 23, 2012
  40. chemistry

    1. Calculate the standard enthalpy change for the reaction: C2H4(g) + H2(g) → C2H6(g) given that the enthalpy of combustion for the reactants and products are: ΔHºc(C2H4)(g) = -1411 kJ mol^-1 ΔHºc(C2H6)(g) = -1560 kJ mol^-1 ΔHºc(H2)(g) = -286 kJ

    asked on July 19, 2014
  41. Chemistry

    I've tried to solve this question multiple ways I just can't seem to get it. I just don't understand what I should be doing. An organic liquid is a mixture of methyl alcohol () and ethyl alcohol (). A 0.220- sample of the liquid is burned in an excess of

    asked on September 16, 2012
  42. algebra

    Homer is giving some cookies to each of his three brothers. To the oldest, he gives half of the cookies and half a cookie. He then gives half of what is now left and half a cookie to his second brother. Finally, he gives half of what is now left and half a

    asked on November 24, 2009
  43. English

    Parenthetical expressions include information that may be helpful but are not essential to the meaning of a sentence. They are de-emphasized by ________. A. dashes B. parentheses C. commas D. brackets I'm not really understanding this question. It has to

    asked on February 13, 2015
  44. Statistics

    Suppose a certain species bird has an average weight of xbar 3.40 grams. Based on previous studies, we can assume that the weights of these birds have a normal distribution with sigma 0.29 grams. Find the sample size necessary for a 98% confidence level

    asked on July 16, 2010
  45. chemistry

    Treatment of gold metal with BrF3 and KF produces Br2 and KAuF4, a salt of gold. Find the mass of the gold salt that forms when a 73.0 -g mixture of equal masses of all three reactants is prepared.

    asked on November 2, 2010
  46. Math

    Which is likely to have a mass close to 2 kilograms A.a grown elephant B.a pineapple C.a 3-year old child** acron

    asked on March 27, 2018
  47. Physics

    A police car traveling at 94.5 km/h is traveling west, chasing a motorist traveling at 77.2 km/h. (a) What is the velocity of the motorist relative to the police car? The magnitude and its direction (b) What is the velocity of the police car relative to

    asked on August 1, 2012
  48. calculus

    At noon, ship A is 110 km west of ship B. Ship A is sailing east at 25 km/h and ship B is sailing north at 15 km/h. How fast is the distance between the ships changing at 4:00 PM?

    asked on October 13, 2011
  49. Geography

    Where can I find all the information I need regarding a specific North American State? Example: Florida...What is the State motto, flower, capital etc...

    asked on November 3, 2009

    A mixture of Xe, Kr, and Ar has a total pressure of 6.7 atm. What is the mole fraction of Kr if the partial pressures of XE and Ar are 1.6 atm and 2.8 atm? Did anyone get .343 ?

    asked on May 12, 2012
  51. chemistry

    Some distilled water is added to an empty beaker. A gram of copper(II) nitrate is added to the beaker with stirring. After a few minutes, what is in the beaker? a. solid copper(II) nitrate and water b. nitrogen gas, copper atoms, electrons, and water c. a

    asked on January 28, 2011
  52. English expression

    1. He is of medium height. 2. He is of average weight. 3. He has medium height. 4. He has average weight. 5. He has long curved hair. 6. She has short straight blond hair. 7. She has medium-length wavy blonde hair ----------------------------------- Are

    asked on March 23, 2008
  53. MUSIC

    which style period would electronics have the strongest impact on? A)Classical B)Romantic C)Twentieth century D)Baroque

    asked on May 1, 2017
  54. Calculus

    A differential equation that is a function of x only a.will produce a slope field with parallel tangents along the diagonal b.will produce a slope field that does not have rows or columns of parallel tangents c.will produce a slope field with rows of

    asked on February 18, 2016
  55. Chemistry

    Calculate ΔG∘ at 298 K for the following reactions. Ca(s)+CO2(g)+12O2(g)→CaCO3(s) 2KClO3(s)→2KCl(s)+3O2(g) CO(g)+H2O(g)→H2(g)+CO2(g)

    asked on May 18, 2014
  56. math

    On a 28-question test, there are 2-point questions, 4-point questions, and 5-point questions. The test is worth a total of 100 points. There are twice as many 2-point questions as 5-point questions on the test. How many 2-point questions are on the test?

    asked on October 18, 2016
  57. physics

    A nurse pushes a cart by exerting a force on the handle at a downward angle 35.0º below the horizontal. The loaded cart has a mass of 28.0 kg, and the force of friction is 60.0 N. (a) Draw a free-body diagram for the system of interest. (b) What force

    asked on September 18, 2012
  58. Fraction

    A girl spends 1/4 of her pocket money on monday and 3/8 on wednesday. What fraction of her money is left

    asked on November 3, 2014
  59. Physics

    You toss a tennis ball straight upward. At the moment it leaves your hand it is at a height of 1.5 m above the ground, and it is moving at a speed of 8.0 m/s. (a) How much time does it take for the tennis ball to reach its maximum height? (b) What is the

    asked on September 6, 2014
  60. chemistry

    name each of the following ionic compounds by stock system... couldn't find these in the list. a)NaCl b) KF c) CaS d) Co(NO3)2 e)FePO4 f)Hg2SO4 g) Hg3(PO4)2

    asked on March 2, 2008
  61. clemson

    A farmer wants to make three identical rectangular enclosures along a straight river, as in the diagram shown below. If he has 1680 yards of fence, and if the sides along the river need no fence, what should be the dimensions of each enclosure if the total

    asked on October 6, 2014
  62. calculus

    No idea where to start The cost in dollars of producing x units of a particular camera is C(x) = x2 - 10000. (10 points) Find the average rate of change of C with respect to x when the production level is changed from x = 100 to x = 101. Include units in

    asked on December 16, 2014
  63. S.S

    In the election of 1856, Millard Fillmore was the Know-Nothing candidate and received 21 percent of the popular vote. What conclusion could be drawn from this fact? A. A significant number of people opposed slavery. B. A significant number of people were

    asked on March 7, 2018
  64. science

    How many kilograms of NH3 are needed to produce 1.00 x 10^5 kg of (NH4)2SO4?

    asked on May 23, 2012
  65. Calculus

    dy/dx=x/(x-4) I.will have a slope field with negative slopes in quadrant I II.will have a slope field with positive slopes in all quadrants III.will produce a slope field with columns of parallel tangents

    asked on February 18, 2016
  66. College Math

    A block with a mass of m = 31 kg rests on a frictionless surface and is subject to two forces acting on it. The first force is directed in the negative x-direction with a magnitude of F1 = 11 N. The second has a magnitude of F2 = 22.75 N and acts on the

    asked on October 9, 2014
  67. Math

    In a group of 40 students, 22 study Economics, 25 study Law, and 3 study neither of these subjects. Determine the probability that a randomly chosen student studies: 1. Both Economics and Law 2. At Least one of these subjects 3. Economics given that he or

    asked on October 31, 2017
  68. Chemistry

    Butane, C4H10, is a component of natural gas that is used as fuel for cigarette lighters. The balanced equation of the complete combustion of butane is 2C4H10(g)+13O2(g)→8CO2(g)+10H2O(l) At 1.00 atm and 23 ∘C, what is the volume of carbon dioxide

    asked on May 6, 2014
  69. Chemistry

    Calculate the percent ionization of 0.140 M lactic acid in a solution containing 8.5×10−3 M sodium lactate.

    asked on April 27, 2013
  70. English

    1. What do you usually do after school? I always go to an academy. I always go to my academy. I always go to our academy. I always go to the academy. (Which answer is right and commonly used?) 2. I have a father, a mother, and a sister. 3. I have Father,

    asked on May 20, 2009
  71. chemistry

    Calculate the standard cell potential for each of the electrochemical cells? 2Ag+(aq)+Pb(s)→2Ag(s)+Pb2+(aq) E∘cell......V? 2ClO2(g)+2I−(aq)→2ClO−2(aq)+I2(s) E∘cell......V? O2(g)+4H+(aq)+2Zn(s)→2H2O(l)+2Zn2+(aq) E∘cell......V?

    asked on April 11, 2014
  72. math

    Calculate the finance charge and new balance using the previous balance method. Previous balance = $179.32 Annual rate = 16% Finance charge = New purchases = $117.42 Payments/credits = $85.00 New balance =

    asked on June 14, 2010
  73. S.S

    5. The Underground Railroad used escape routes that went throughout the South. Based on that fact, which of the following conclusions could be made? (1 point) A. The Southern states were leaning toward emancipation of the slaves. B. Slaves were hopeful to

    asked on March 7, 2018
  74. English

    Please say hello to your parents. Give my best wishes to your parents. Give my regards to your parents. Give my best regards to your parents. ------------------------ 1. Are they all the same? Can we add or delete 'best'? 2. He had lunch in a second. (What

    asked on June 26, 2008
  75. calculus

    it costs 8 dollars to manufacture and distribute a backpack.If the backpack sell at x dollar each, the number sold , n, is given by n= 3/(x-8)+5(100-x) . Find the selling price that will maximize the profit.

    asked on November 15, 2014
  76. Chemistry!!!

    Consider the rxn during the Haber Process: N2 + 3H2 ---> 2NH3 The equilibrium constant is 3.9 x 10^(5) at 300 K and 1.2 x 10^(-1) at 500 K. Find Delta H reaction and Delta S for reaction

    asked on April 20, 2012
  77. Math

    Why doesn't Gyro on Even Numbers When Playing Roulette?

    asked on May 10, 2009
  78. science

    How is biodiversity related to human activities that use natural resources? A.biodiversity decreases as humans use natural resources wisely B.biodiversity decreases as humans limit there use of natural resources C.biodiversity increases as humans deplete

    asked on December 9, 2013
  79. Chemistry (URGENT)

    In order to analyze the waste water containing Co^2+ from a manufacturing process, 1.0L of water was evaporated to 10.0mL, then placed in a spectrophotometer tube. The absorbance was found to be 0.20. Using your calibration curve, calculate the number of

    asked on December 16, 2010
  80. Physics

    A truck driver slams on the brakes and skids to a stop through a displacement of delta x. (a) IF the truck has twice the mass, by what factor does the stopping distance change? 1) 0.25 or 2) 1 or 3) 4 (b) If the initial velocity of the truck were halved,

    asked on February 25, 2008
  81. Calculus

    Given the table below for selected values of f(x), use 6 trapezoids to estimate the value of x 1 3 4 6 7 9 10 f(x) 4 8 6 10 10 12 16

    asked on February 19, 2016
  82. Physics Please help!

    Calculate the position of the center of mass of the following pairs of objects. Use acoordinate system where the origin is at the center of the more massive object. Give youranswer not in meters but as a fraction of the radius as requested. Get data from

    asked on February 28, 2012
  83. arkansas history

    where are the major cities located

    asked on January 8, 2019
  84. chemistry

    In a large building, oil is used in a steam boiler heating system. The combustion of 1.0 lb of oil provides 2.2×107J. Part A How many kilograms of oil are needed to heat 110 kg of water from 24 ∘C to 100∘C? (Assume that 1lb=454g, the specific heat of

    asked on September 23, 2016
  85. Physics

    A small disk of radius R1 is mounted coaxially with a larger disk of radius R2. The disks are securely fastened to each other and the combination is free to rotate on a fixed axle that is perpendicular to a horizontal frictionless table top. The rotational

    asked on December 2, 2011
  86. physics

    How does pressure work as a restoring force to create a sound wave?

    asked on April 6, 2011
  87. World history

    Which temporary solution was adopted in 1924 to address the economic problems caused by Germany's inability to make reparations? A-Versailles plan B-Marshall plan C-Dawes plan D-young plan B?

    asked on July 13, 2018
  88. chemistry

    A furnace that provides heat by burning methane gas must have the correct mixture of air and fuel to operate efficiently. What is the mole ratio of air to methane gas in the combustion of methane? Hint: Air is 20% oxygen.

    asked on May 27, 2011
  89. Physics

    A dropping ball initial at rest is dropped 1.5m; calculate a) the traveling time of the ball and b) its velocity just before reaching the ground.

    asked on February 10, 2013
  90. physics

    Catching a wave, a 77-kg surfer starts with a speed of 1.1 m/s, drops through a height of 1.60 m, and ends with a speed of 8.5 m/s. How much nonconservative work was done on the surfer?

    asked on March 22, 2011
  91. math

    A confectioner has 300 pounds of a chocolate that is 1 part cocoa butter to 7 parts caramel. How much chocolate that is 1 part cocoa butter to 15 parts caramel should be combined with the first in order to create a new chocolate that is 1 part cocoa butter

    asked on March 5, 2016
  92. Calculus

    ABC Daycare wants to build a fence to enclose a rectangular playground. The area of the playground is 900 square feet. The fence along three of the sides costs $5 per foot and the fence along the fourth side, which will be made of brick, costs $10 per

    asked on April 13, 2014
  93. another question algebra

    write an explicit formula for the sequence 7,2,-3,-8,-13 then find a14

    asked on June 9, 2008
  94. Trig

    If sin a=0.31 cos a=0.95 sin b=0.47 and cos b=0.88 what is sin (a+b)? 0.78 -0.17 0.98 0.72

    asked on April 23, 2018
  95. chemistry proofread

    write the chemical equations for the following sentences a) Aluminum reacts with oxygen to produce aluminum oxide I put Al + O2 ----------> 2Al2O3 b) Phosphoric acid, H3PO4, is produced through the reaction between tetraphosphorous decoxide and water I put

    asked on March 26, 2008
  96. physics

    a 2 kilogram rifle initially at rest fires a 0.002 kilogram bullet. as the bullet leaves the rifle with a velocity of 500 meters per second, what is the momentum of the rifle bullet system? isn't the answer one because final momentum minus initial momentum

    asked on January 6, 2011
  97. English

    What belief does Whitman share with Ralph Waldo Emerson and other transcendentalists? A) We should live our lives well to achieve everlasting happiness. B) Man learns his most important lessons and insights in the present, through direct experience. If I

    asked on January 8, 2015
  98. Math

    Let f(x) be a polynomial such that f(cos theta) = cos(4 theta) for all theta. Find f(x). (This is essentially the same as finding cos(4 theta) in terms of cos theta; we structure the problem this way so that you can answer as a polynomial. Be sure to write

    asked on February 8, 2014
  99. Physics

    In Figure 9-61, block 1 (mass 2.0 kg) is moving rightward at 8 m/s and block 2 (mass 4.8 kg) is moving rightward at 2.8 m/s. The surface is frictionless, and a spring with spring constant of 1180 N/m is fixed to block 2. When the blocks collide, the

    asked on December 10, 2012
  100. Chemistry help please!!!

    Experimental Procedure, Part F. A 1.0- mL volume of 0.010 M H2SO3 is added to a mixture of 12 drops of 0.01 M HIO3, 8 drops of deionized water, and 1 drop of starch solution. A color change in the reaction mixture occured in 40 seconds. a. Assuming 25

    asked on January 27, 2011