Popular questions and responses by lindsay
  1. math

    The 9th term of an AP is 8 and the 4th term is 20. Find the first term and the common difference.

    asked on April 6, 2013
  2. chemistry! URGENT

    A standard solution is prepared for the analysis of fluoxymesterone (C20H29FO3), an anabolic steroid. A stock solution is first prepared by dissolving 10.0 mg of fluoxymestrone in enough water to give a total volume of 500.0 ml. A 100.0 micro liter aliquot

    asked on December 7, 2011
  3. Math

    The first row of a concert hall has 25 seats and each row after the first has one more seat than the row before it. There are 2 rows of seat. 1)Write a rule for the number of seats in the nth row. 2)35 students from a class want to sit in the same row. How

    asked on March 2, 2010
  4. Physics

    By what factor is the resistance of a copper wire changing when its temperature is increased from 20 degrees Celsius to 120 degrees Celsius? The temperature coefficient of resistivity for copper = 3.9 x 10^-3 (C)^-1.

    asked on February 5, 2012
  5. math

    An A.P. is given by k,2k/3,k/3, 0,... Find the 6th term.

    asked on July 22, 2014
  6. Finance

    Quad Enterprises is considering a new three-year expansion project that requires an initial fixed asset investment of $2.38 million. The fixed asset falls into the three-year MACRS class (MACRS schedule). The project is estimated to generate $1,760,000 in

    asked on April 5, 2020
  7. algebra

    Find 1.The first 4 terms of the binomial expansion in ascending powers of x of (1+x/4)^8. 2.Use your expansion to estimate (1.025)^8

    asked on July 22, 2014
  8. Math

    Find the value of x if line QS bisects angle PQR and measure of angle PQR equals 82 degrees. angle PQS=10x+1

    asked on October 30, 2016
  9. Physics II

    A large cylindrical water tank 11.5 m in diameter and 13.5 m tall is supported 8.75 m above the ground by a stand. The water level in the tank is 10.6 m deep. The density of the water in the tank is 1.00 g/cm3. A very small hole is formed at the base of

    asked on January 18, 2015
  10. math

    The sum of the first 20 terms of an arithmetic series is identical to the sum of the first 22 terms. If the common difference is -2, find the first term.

    asked on July 17, 2014
  11. math

    Solve the equation 3^2x - 12 x 3^x + 27 = 0

    asked on July 19, 2012
  12. trigonometry

    Find all the angles between 0 degrees and 360 degrees which satisfy the equations a. 8 cos x sin x = sin x b. 5 tan^2 y + 5 tan y = 2 sec^2 y.

    asked on April 21, 2012
  13. trigonometry

    given triangle ABC with AB=7cm, BC=8cm and AC=9cm calculate 1. the size of the largest angle 2. the area of the triangle

    asked on April 21, 2012
  14. Physics

    A bus travels 280 km south along a straight path with an average velocity of 88 km/hr to the south. The bus stops for 24 min, then it travels 210 km south with an average of 75 km/hr to the south. A. How long does the total trip last? B. What is the

    asked on September 10, 2007
  15. Physics

    A bowling ball traveling with constant speed hits the pins at the end of a bowling lane 16.5 m long. The bowler hears the sound of the ball hitting the pins 2.51s after the ball is released from his hands. What is the speed of the ball? The speed of sound

    asked on August 30, 2013
  16. Calculus (check my work)

    The measurement of the circumference of a circle is found to be 64 centimeters, with a possible error of 0.9 centimeter. Approximate the percent error in computing the area of the circle. MY ANSWER 8.83%

    asked on December 17, 2013
  17. Chemistry

    Draw the condensed structural formula for the products of the acid hydrolysis of the following amide with HCl: CH3-CH2-C(=O)-NH2 + H2O + HCl ---> I'm afraid I don't even know where to begin with this one, help!

    asked on November 24, 2010
  18. Stastics

    Which of the following descriptions of confidence intervals is correct? (Select all that apply) a. If a 95% confidence interval contains 0, then the 99% confidence interval contains 0 b. If a 99% confidence interval contains 0, then the 95% confidence

    asked on April 25, 2016
  19. math

    Given that 2 log base2 (x+15) - log base2 x = 6 1.Show that x^2 -34x +225 = 0 2. Hence or otherwise solve the equation 2 log base 2 (x+15) - log base 2 x =6

    asked on July 10, 2014
  20. math

    a species of orchid is being studied. The population 'p' at time 't' years after the study started is assumed to be p = 2800ae^0.2t/1 + ae^0.2t where 'a' is a constant. Given tnat there were 300 orchids when the study started. a. show that a =0.12 b. use

    asked on March 18, 2013
  21. trigonometry

    solve the equation: 4 tan^2 x + 12 sec x +1 =0, for 0 degrees is less than or equal to x is less than or equal to 360 degrees.

    asked on May 1, 2012
  22. Physics

    A basketball player, standing near the basket to grab a rebound, jumps 73.6 cm vertically. How much time does the player spend in the bottom 15.4 cm of the jump? Ok...after this I swear I'm done! I just need someone to check my final answer, which is

    asked on October 10, 2007
  23. Calculus (check my answer)

    The measurement of the edge of a cube is found to be 15 inches, with a possible error of 0.03 inch. Use differentials to approximate the maximum possible propagated error in computing the surface area of the cube. I got 5.4 inches squared. Is this right?

    asked on December 17, 2013
  24. Calculus

    The measurements of the base and altitude of a triangle are found to be 36 and 50 centimeters, respectively. The possible error in each measurement is 0.25 centimeter. Use differentials to approximate the possible propagated error in computing the area of

    asked on December 16, 2013
  25. Calculus

    Y=5x^4 -24x^3+24x^2+17 is concave down for which interval? A) x0 C) x-2/5 D) x2 E) 2/5 < x < 2 I know you take the second derivative...but I keep getting stuck with something that won't factor right?

    asked on December 9, 2013
  26. calculus anti-derivation

    Given that the graph of f(x) passes through the point (2,5) and that the slope of its tangent line at (x, f(x))is 3x+5, what is f(3) ?

    asked on April 14, 2012
  27. Physics

    A long thin rod of mass M = 2:00 kg and length L = 75:0 cm is free to rotate about its center as shown. Two identical masses (each of mass m = .403 kg) slide without friction along the rod. The two masses begin at the rod's point of rotation when the rod

    asked on December 24, 2011
  28. Chemistry

    How much Ba(OH)2 is needed to neutralize 3.2 moles of H2SO4 and 4.5 moles of HCl mixed together in 755 mL of water?

    asked on October 24, 2010
  29. Calculus (check my answers)

    10) Use the information to evaluate and compare delta y and dy. y=2-x^4, x=2 and delta x=dx=0.01 MY ANSWER: dy=-.32 and delta y=-.3224. Are they supposed to be negative, and how do I compare those in words? I don't even understand what I was supposed to

    asked on December 17, 2013
  30. Trigonometry

    1. ((cosx)/(1 + sinx))+((1 + sinx)/(cosx)) 2. ((cos(x)cot(x))/(1 - sin(x)))-1

    asked on July 16, 2012
  31. geometry

    the diagonal VY of a cuboid =root(26.25)cm, the length of a side ZY = 4cm and the height of a sideUZ =25cm for the cuboid. Find the width of the width UV.

    asked on April 24, 2012
  32. trigonometry

    Find the general solution for f(x) = 27 tan^2 x-9=0

    asked on April 23, 2012
  33. Chemistry

    Choose the true statements regarding the charge-minimized Lewis structure(s) of the BrO2- ion. (selet all that apply) a. There is only one charge-minimized structure for this ion. b. There are two charge-minimized resonance structures for this ion. c. The

    asked on October 5, 2008
  34. Physics

    A robot probe drops a camera off the rim of a 239 m high cliff on Mars, where the free-fall acceleration is -3.7 m/s^2. a) Find the velocity with which the camera hits the ground. b) Find the time required for it to hit the ground. Ok so I'm not even sure

    asked on September 25, 2007
  35. math

    solve the equation for x. 3^2x - 3^x+2 +8 =0 Ps. The topic is logarithmic and exponential functions

    asked on May 25, 2014
  36. math

    0.06 2/3 into a fraction

    asked on February 7, 2014
  37. Calculus

    Please, don't assume that we've been taught this stuff because we were literally just handed a packet and told to learn it ourselves. I don't understand this in the slightest. The question is: Use the information to evaluate and compare delta y and dy.

    asked on December 16, 2013
  38. trigonometry

    A sector AOB of a circle, centre O, radius r cm, where the acute angle AOB is theta radians. Given that the perimeter of the sector is 14 cm and that the area of the sector is 10 cm^2, evaluate r and theta.

    asked on March 8, 2013
  39. Economics

    We're looking at the market for cat food. When the price is $10, the quantity sold is 1000 bags. When the price drops 10%, the quantity sold increases 30%. Calculate the price elasticity of demand. (Answer in format X.XX, round to the nearest hundredth.) I

    asked on February 25, 2013
  40. trigonometry

    two pieces of wire stretched from the top, M of a vertical pole to the points L and N on the horizontal ground. the angle of depression of L from N =65 degrees. N is on the opposite side of the pole(from left)at an angle of depression of 72 degrees from M.

    asked on April 23, 2012
  41. physics

    In order to change the angular momentum of an object, it is necessary to apply a. a net force to the object. b. a net torque to the object. c. a centripetal acceleration to the object. d. both a net force and a net torque to the object. We have three

    asked on December 24, 2011
  42. Physics

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

    asked on December 15, 2011
  43. Chemistry

    All amino acids (choose the correct choice) a) have the same side chains b) form zwitterions c) have the same isoelectric points d) show hydrophobic tendencies e) are essential amino acids

    asked on December 13, 2010
  44. Math

    The equation of a circle is x^2-6x+y^2+2y=15 what is the center and the radius?

    asked on September 12, 2010
  45. physics

    What is the temperature of an ideal gas whose molecules have an average translational kinetic energy of 3.90 10-20 J? K

    asked on April 12, 2010
  46. Chemistry II

    What is the process that occurs when solvent molecules surround a solute?

    asked on September 9, 2009
  47. History

    Compare and contrast the American and french revolution

    asked on June 3, 2009
  48. Chemistry

    Im's So confused about stoichiometry. My question is this use stoichiometric calculations to predict the mass of solid product fromed in the reaction from the knwon mass of sodium hydrogen carbonate used. Balenced equation: 4NaHCO3 = 4Na + 2H2O + 4CO + 3O2

    asked on November 1, 2008
  49. Physics

    An archer shoots an arrow that leaves the bow at an angle of 42 degrees above the horizontal. The arrow hits a target located 135 m away and 23 m above the height from which the arrow was shot. Given that the mass of the arrow is .125 kg and that it

    asked on January 16, 2008
  50. Algebra

    Could you explain to me how to these type of problems? I checked in my book and it is still confusing. Evalute the piecewise function at the given value of the independent variable. 1. g(x)= {x^2+2 if x cannont equal 2, x+8 if x=2 Determine g(-5). 2. f(x)

    asked on August 30, 2007
  51. Chemistry

    In the synthesis of asprin we react salicylic acid (HOOCC6H4OH) with acetic anhydride (C4H6O3) . The unbalanced chemical equation is: HOOCC6H4OH + C4H6O3 --> HOOCC6H4O2C2H3 + H2O If we mix together 28.2 g of salicylic acids with 15.6 g of acetic anhydride

    asked on September 24, 2017
  52. Mathmatics

    I want to be able to have $50,000 a year during retirement. I want to make sure that I can have it until I am 100 years old. I plan to retire at 65. I can earn 6%. How much do I need to have at retirement to be able to make it?

    asked on August 18, 2015
  53. calculus

    Simplify the following power functions to the form y=kxp, where k and p are some numbers. (a) y=(18)/x√ is y=kxp. What are k and p?

    asked on February 5, 2015
  54. physics

    The electron in a certain hydrogen atom has an angular momentum of 6.834 × 10-34 J·s. What is the largest possible magnitude for the z component of the angular momentum of this electron? For accuracy, use h = 6.626 × 10-34 J·s. I know you need to use

    asked on July 23, 2014
  55. Stats.

    Another one that I need help.... At Ajax Spring Water, a half-liter bottle of soft drink is supposed to contain a mean of 520 ml. The filling process follows a normal distribution with a known process standard deviation of 4 ml. (a) Which sampling

    asked on April 23, 2014
  56. Journalism

    I tried writing the opening to my article on vegetarianism and this is what I got so far. [A lot of people like to sit down at night and eat a big, juicy steak – and then there are those who prefer an organic meal without any meat. Vegetarianism is not

    asked on October 6, 2013
  57. Journalism

    I've started working on an article for my Journalism class about vegetarianism - pros and cons, and why or why not people at my school support it. I've gotten a few paragraphs in, but I'm having trouble on writing the lead. Any suggestions?

    asked on October 6, 2013
  58. Math

    Describe the intervals on which the following function is continuous. If not continuous, state "where" the discontinuity occurs and state the TYPE of discontinuity. f(x)= (x^2-x-12)/(x^2-6x+8) I just don't understand how to find the intervals. Thanks~

    asked on August 20, 2013
  59. math

    Find the exact value of 1. tan 75 degrees 2. Cos 15 degrees 3. Sin 105 degrees

    asked on May 21, 2013
  60. math

    If the bearing fron H to G is 098 degrees, what is the bearing of G from H

    asked on May 18, 2013
  61. math

    Three students, Chris, Vlad, and Steve, are registered for the same class and attend independently of each other. If Chris is in class 80% of the time, Vlad is in class 85% of the time, and Steve is in class 90% of the time, what is the probability that at

    asked on April 21, 2013
  62. math

    a cyclist travels the 30 km from Town A to Town B at an average speed of 25 km/h and immediately continues the journey to town C, which is a further 60 km away at an average speed of 20 km/h. What is the average speed for the whole journey?

    asked on November 23, 2012
  63. math

    simplify the following giving your answer with a rational denominator, 2 root3 - root 3/ 2 + root three.

    asked on July 19, 2012
  64. physics

    to start a nuclear fusion reaction, two hydrogen atoms of charge 1.602x10^-19 and mass 1.67x10^-27kg must be fired at each other. If each particle has an initial velocity of 2.7x10^6m/s when released, what is their minimum seperation?

    asked on June 11, 2012
  65. physics

    a square with side length 2.0 cm has a charge of -1.0x10^-6C at every corner. What is the magnitude and direction of the electric force on each charge? What is the force on a fifth charge placed in the centre of this square? Does the sign of the fifth

    asked on June 7, 2012
  66. trigonometry

    show that sin 2theta/1-cos 2 theta = cot theta

    asked on April 24, 2012
  67. trigonometry

    Hal walked from point A to point B due north east from a distance of 20m. He immediately changed direction and walked 50m from B to C on a bearing of 110 degrees. 1. calculate the distance AC 2. Find the bearing of C from A

    asked on April 23, 2012
  68. trigonometry

    a ship travels 8km due north then 7km on a bearing of 070 degrees 1. draw a diagram to represent the information 2. calculate the distance and bearing of the ship from its starting point

    asked on April 21, 2012
  69. spanish

    This is on demonstrative adjectives and are fill in the blanks. ____ pantolones son bonitos y el precio no es muy alto. Si, las dos cosas son geniales. Tambien me gustan ____ sueteres que estan cerca de ti. ?De que talla es _____ sueter negro, el de solo

    asked on January 19, 2012
  70. geometry

    Triangles Rst and wxy are similar . the side lengths of rst are 10 inches. 14 inches and 20 inches and the length of an altitude is 6.5 inches. The shortest side of wxy. Find the lengths of the other two sides of wxy. Find the length of the corresponding

    asked on January 12, 2012
  71. Physics

    A star with the same mass and diameter as the sun rotates about a central axis with a period of about 29.2 days. Suppose that the sun runs out of nuclear fuel and collapses to form a white dwarf star with a diameter equal to that of the earth. Assume the

    asked on December 23, 2011
  72. Physics

    An airplane of mass 2180 kg located 131 km north of U is ying 272 km/hr in an easterly direction. (a) What is the magnitude of the angular momentum (kg m2/s) with respect to U? (b)what is the angular momentum with respect to U?

    asked on December 23, 2011
  73. chemistry

    When zinc metal is reacted with hydrochloric acid, zinc chloride and hydrogen gas are produced. If 16.4 ml of 2.14 M HCl are used: a) how many grams of zinc metal are needed to completely use up the acid? b) What will be the molarity of the aqueous

    asked on December 7, 2011
  74. Calculus

    Find the Derivative of the function: f(x)= ln(x^2/2x-3)

    asked on November 7, 2011
  75. statistics

    A sales firm receives an average of four calls per hour on its toll-free number. For any given hour, find the probability that it will receive exactly eight calls

    asked on August 3, 2011
  76. Chem

    Please tell me if these are right? A mixture of oxygen and helium is prepared for a scuba diver that will descend to 125 feet below the ocean surface. At that depth the diver breathes a gas mixture that has a total pressure of 8atm. If the particle

    asked on November 29, 2010
  77. Chemistry

    I know that vanillin has the functional groups aldehyde, ether, and phenol. My assigment says there is a fourth. Which one am I missing?

    asked on November 24, 2010
  78. arithmetic

    Find the sum of the first 40 terms of the arithmetic sequence. 19, 24, 29, 34

    asked on November 17, 2010
  79. Math

    A vet surveys 26 of his patrons. He discovers that 14 have dogs. 10 have cats. 5 have fish. 4 have dogs & cats. 3 have dogs & fish. 1 has a cat & a fish. Use a diagram to answer the following question: If no one has all 3 kinds of pets, how many patrons

    asked on March 3, 2010
  80. math

    You want to estimate 5.25-3.3 why would using front-end estimation tell you more about the answer than rounding?

    asked on November 10, 2009
  81. Chemistry II

    When dissolved in water, ammonium phosphate would have a value of __________ for i solute.

    asked on September 9, 2009
  82. Chemistry II

    If the freezing point depression (DTf) is 5.62 and the freezing point depression constant (Kf) is 3.90, what is the molality of the solution? Assume that the solute is a nonelectrolyte (i = 1).

    asked on September 8, 2009
  83. Chemistry

    considering the polarity of each compound and that of a solvent in which it is dissolved (including the potential for hydrogen bonding), give a brief explanation of each result: a) biphenyl in hexane - which is also soluble b) biphenyl in methyl alcohol -

    asked on February 5, 2009
  84. Chemistry

    considering the polarity of each compound and that of a solvent in which it is dissolved (including the potential for hydrogen bonding), give a brief explanation of each result: a) malonic acid in water - which i know is soluble b) malonic acid in hexane -

    asked on February 5, 2009
  85. Physics

    -An object whose height is 5.8 cm is at a distance of 9.5 cm from a spherical concave mirror. Its image is real and has a height of 9.2 cm. Calculate the radius of curvature of the mirror. I got 0.1165 m for my answer. -How far from the mirror is it

    asked on May 27, 2008
  86. Physics

    My question had 2 parts: a) A 2.0 kg object oscillates with simple harmonic motion on a spring of force constant 580.0 N/m. The maximum speed is 1.0 m/s. What is the total energy of the object and the spring? Answer: 1.0 J b) What is the maximum amplitude

    asked on April 30, 2008
  87. Physics

    A lead ball, with an initial temperature of 25.0oC, is released from a height of 96.0 m. It does not bounce when it hits a hard surface. Assume all the energy of the fall goes into heating the lead. Find the temperature (in degrees C) of the ball after it

    asked on March 30, 2008
  88. Physics

    In a certain process, 2.11x10^5 J of heat are supplied to a system and at the same time, the system expands against a constant external pressure of 6.89x10^5 Pa. Given that the temperature of the system does not change, find the increase in volume of the

    asked on March 26, 2008
  89. Astronomy

    If you lived on Mars, which planets would describe retrograde loops? Which would never be visible as crecent phases?

    asked on March 17, 2008
  90. math-algebra

    x=3y-4 2x-y=7 solve as a set/substitution.

    asked on July 11, 2008
  91. Physics

    A research balloon of total mass 200 kg is descending vertically with a downward acceleration of 3.2 m/s^2. How much ballast must be thrown from the car to give the balloon an upward acceleration equal to 2.8 m/s^2, presuming that the upward lift of the

    asked on November 28, 2007
  92. Physics

    A small steel ball bearing with a mass of 24 g is on a short compressed spring. When aimed vertically and suddenly released, the spring sends the bearing to a height of 1.23 m. Calculate the horizontal distance the ball will travel if the same spring is

    asked on November 4, 2007
  93. Physics

    It takes 2.5 s for a small ball released from rest from a tall building to reach the ground. The mass of the ball is 0.05 kg. Calculate the height from which the ball is released. Ok so I have the time, initial velocity, and the acceleration. But the mass

    asked on October 9, 2007
  94. Physics

    A stone is thrown vertically upward. On its way up it passes point A with speed v, and point B, 12.6 m higher than A, with speed v/2. Calculate the maximum height reached by the stone above point B. I was told the equation to this was "h=1/2(v2)^2/g."

    asked on October 7, 2007
  95. Physics

    A golf ball released from a height of 1.80 m above a concrete floor, bounces back to a height of 1.06 m. If the ball is in contact with the floor for 4.62 ms, what is the magnitude of the average acceleration a of the ball while it is in contact with the

    asked on October 4, 2007
  96. Chemistry

    These are all true or false questions, and I think some of my answers may be wrong. Could someone please check them for me? 1) All stoichiometry calculations are based on STP conditions. (True) 2. Given the amount of reactant, you must use coefficients

    asked on June 4, 2007
  97. More Algebra 2

    It would be great if, again, someone would check these answers for accuracy. I'd like to know if I'm doing them right. 1) What equation defines an exponential decay function? a) y=x^pi b) y=pi^-x c) y=(1/pi)^-x d) y=pi times x I think the answer is c. 2)

    asked on May 23, 2007
  98. Chemistry

    A 63 gram block of an unknown metal at 88 degrees C was dropped into an insulated flask containing approx. 30 g of ice and 30 g of water at 0 degrees C. After the system had reached a steady temp. it was determined that 12.1 g of ice had melted. What is

    asked on May 15, 2007
  99. Chem help!!

    A rock salt (NaCl), ice, and water mixutre is used to make homemade ice cream. How many grams of rock salt must be added to lower the freezing point 10.0 degrees C? I have no idea what to do, please help! delta T = Kf*i*m delta T = 10. Kf is the molal

    asked on May 3, 2007
  100. Math

    Please help find the next 3 numbers in the pattern. 3,2,5,7,19,26 We can’t figure out the pattern.

    asked on April 17, 2020


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