Most popular questions and responses by lindsay
  1. 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
  2. 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
  3. English

    Ebenezer Scrooge’s character changes between Act 1 and Act 2 of A Christmas Carol: Scrooge and Marley. In an essay, describe these changes and analyze how events in the plot shape Scrooge’s character. Include details from the text in your essay.

    asked on May 28, 2018
  4. 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
  5. 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
  6. Calculus

    The total stopping distance T of a vehicle is T=2.5x+0.5x^2 where T is in feet and x is the speed in miles per hour. Approximate the change and percent change in total stopping distance as sped changes from x=25 to x=26 miles per hour. I started taking the

    asked on December 17, 2013
  7. 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
  8. 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
  9. 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
  10. Physics

    A steam engine's boiler completely converts 155 kg of water to steam. This process involves the transfer of 3.5 x 10^8 J by heat. If steam escaping a safety valve does 1.76 x 10^8 J of work against the outside atmosphere, what is the net internal energy of

    asked on March 26, 2008
  11. 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
  12. Ochem

    A student needed to determine the percent composition of a mixture that contained fluorene and benzoic acid. The student took 283 mg of the mixture and used the extraction method to separate the components. Then both compounds were recrystallized and

    asked on October 19, 2011
  13. 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
  14. 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
  15. Physics. Really stuck!

    two blocks of masses m1 and m2 (m1>m2) are placed on a frictionless table in contact with each other. A horizontal force of magnitude F is applied to the block of mass m1. if P is the magnitude of the contact force between the blocks, what are the net

    asked on October 8, 2012
  16. 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
  17. 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
  18. 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
  19. Geometry

    Find the point, M, that divides segment AB into a ratio of 3:2 if A is at (0, 15) and B is at (20, 0).

    asked on September 17, 2016
  20. math

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

    asked on July 22, 2014
  21. math

    a woman's long jump record is about 1 1/6 the distance of the 15-16-year-old girl's record of 20 13/14 feet. find the distance of the women's record to the nearest foot

    asked on January 9, 2019
  22. Physics

    A bullet with a mass m = 4:83 g and initial speed of 330 m/s passes through a wheel which is initially at rest as in the The wheel is a solid disk with mass M = 2.29 kg and radius R = 1.:6 cm. The wheel rotates freely about an axis through its center and

    asked on December 25, 2011
  23. 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
  24. 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
  25. Physics !

    Sound enters the ear, travels through the auditory canal, and reaches the eardrum. The auditory canal is approximately a tube open at only one end. The other end is closed by the eardrum. A typical length for the auditory canal in an adult is about 2.6 cm.

    asked on January 26, 2010
  26. chemistry

    Write the expression for Kc and Kp for the reaction PH3BCl3(s) PH3(g) + BCl3(g)

    asked on March 8, 2012
  27. 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
  28. 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
  29. physics

    The drawing shows an equilateral triangle, each side of which has a length of 4.53 cm. Point charges are fixed to each corner, as shown. The 4.00 C charge experiences a net force due to the charges qA and qB. This net force points vertically downward and

    asked on June 17, 2014
  30. 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
  31. math

    Four bottles of water and 3 bagels cost $10.94. At the same prices, 3 bottles of water and 6 bagels cost $11.28. Find the price per bottle of water and the price per bagel.

    asked on April 15, 2019
  32. physics

    a metal ball with a charge of 5.4x10^8 electrons is touched to another metal ball so that all the excess electrons are shared equally. What is the final cahrge on the first ball?

    asked on June 7, 2012
  33. 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
  34. Physics

    The Wall of Death in an amusement park is comprised of a vertical cylinder that can spin around the vertical axis. Riders stand against the wall of the spinning cylinder and the floor falls away leaving the riders held up by friction. The radius of the

    asked on December 15, 2007
  35. 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
  36. Physics

    A stone is thrown vertically upward with a speed of 19.0m/s How fast is it moving when it reaches a height of 10.0m

    asked on August 29, 2013
  37. Physics

    A regulation volleyball court is L = 18.0 m long and a regulation volleyball net is d = 2.43 m high. A volleyball player strikes the ball a height h = 1.76 m directly above the back line, and the ball's initial velocity makes an angle q = 55° with respect

    asked on November 8, 2007
  38. math

    A paperweight containing liquid is made up of a cone and a cylinder. The radius of the cone is 3cm with height of 4cm. The diameter is 20cm and height is 8cm. 1. Calculate the total volume of the cone and cylinder when it si empty, leaving your answer in

    asked on November 29, 2012
  39. Stastics

    Can someone help me and let me know if what I have solved is correct. A researcher randomly surveyed 300 high school seniors and determined 225 stated they drive a car to high school. We are interested in the population proportion of seniors who drive a

    asked on April 24, 2016
  40. 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
  41. Physics/ Chem

    Find the entropy change when 51g of steam condenses to water at 100 ∘C.

    asked on April 22, 2014
  42. 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
  43. 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
  44. 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
  45. statistics

    A survey was conducted to measure the number of hours per week adults spend on home computers. In the survey, the number of hours was normally distributed, with a mean of 8 hours and a standard deviation of 1 hour. A survey participant is randomly

    asked on November 7, 2011
  46. Physics

    A quarterback claims that he can throw the football a horizontal distance of 183 m (200 yd). Furthermore, he claims that he can do this by launching the ball at the relatively low angle of 35° above the horizontal. To evaluate his claim, determine the

    asked on February 9, 2011
  47. 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
  48. 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
  49. Physics

    An artillery shell is fired with an initial velocity of 300m/s at 55.0 degrees above the horizontal. To clear an avalanche, it explodes on a mountainside 42.0s later. What are the x and y coordinates of the shell where it explodes, relative to its firing

    asked on October 9, 2012
  50. Physics

    A hockey puck is sliding across a frozen pond with an initial speed of 6.5 m/s. It comes to rest after sliding a distance of 7.6 m. What is the coefficient of kinetic friction between the puck and the ice? I know this one is not that difficult. However, I

    asked on December 5, 2007
  51. 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
  52. trigonometry

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

    asked on April 23, 2012
  53. 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
  54. 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
  55. physics

    Given that the distancef rom Earth to the Moon is 3.8 x 10^8 m, that the Moon takes 27 days to orbit Earth, and that the mass of the Moon is 7.4 x 10^22 kg, what is the acceleration of the Moon and the size of the attractive force between Earth and Moon?

    asked on September 18, 2006
  56. 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
  57. 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 top 15.4 cm of his jump? I never know which formula to use for these problems! Any help will be greatly appreciated.

    asked on October 9, 2007
  58. 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
  59. Physics

    A car traveling at a constant speed of 125 km/hr passes a trooper hidden behind a billboard. One second after the speeding car passes the billboard, the trooper sets in a chase after the car with a constant acceleration of 2.7 m/s^2. How far does the

    asked on January 13, 2008
  60. 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
  61. 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
  62. 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
  63. Chemistry 3

    How is it possible for me to tell which of these solutes will produce an acidic solution when dissolved in water? LiOH CH3CO2K H2SO3 KOH NaOH NH4NO3 NaOH NaOH can't be the only one... Molecules that produce OH^- when dissolved in water will be basic.

    asked on May 24, 2007
  64. English

    Would lonely or isolated be considered character trait

    asked on November 11, 2014
  65. Stats.

    I don't know where to begin with this one.... When told that over a 10-year period a mammogram test has a false positive rate of 50 percent, Bob said "That means that about half the women tested actually have no cancer". Correct Bob's mistaken

    asked on April 23, 2014
  66. math

    Dave walked from point A to point B due North East for a distance of 20m. He immediately changed direction and walked 50m from B to C on a bearing of 110 degrees. i. Calculate the distance AC ii. Find the bearing of C from A

    asked on May 21, 2013

    A car is safely negotiating an unbanked circular turn at a speed of 29 m/s. The road is dry, and the maximum static frictional force acts on the tires. Suddenly a long wet patch in the road decreases the maximum static frictional force to one-ninth of its

    asked on October 2, 2012
  68. trigonometry

    In the triangle ABC, the sides AB and BC have lengths 7cm and 8cm respectively, and angle B is obtuse. the area of the triangle is 14 root 3 cm^2. Find a.The size of angle B b. The length of AC

    asked on May 3, 2012
  69. 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
  70. Chemistry II

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

    asked on September 9, 2009
  71. 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
  72. 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
  73. 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
  74. 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
  75. 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
  76. physics

    A 58.4-kg person, running horizontally with a velocity of +3.84 m/s, jumps onto a 10.7-kg sled that is initially at rest. (a) Ignoring the effects of friction during the collision, find the velocity of the sled and person as they move away. (Indicate the

    asked on October 22, 2012
  77. 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
  78. chem

    The mass of an electron is 9.11\times 10^{-31}~\rm kg. If the de Broglie wavelength for an electron in a hydrogen atom is 3.31\times 10^{-10}~\rm m, how fast is the electron moving relative to the speed of light? The speed of light is 3.00\times10^8 ~\rm

    asked on November 2, 2011
  79. Chemistry 2

    Can someone please tell me which of the following I have wrong?? I know that one or more is incorrect, but I'm not sure which ones... Match the following Bronsted acids with their conjugate bases. Choices: SO42-, SO32-, CO32-, HPO42-, HPO32-, Cl-, F-,

    asked on May 24, 2007
  80. 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
  81. 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
  82. 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
  83. 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
  84. Chemistry

    In a titration experiment 34.12 mL of 0.902 M KOH is reacted with H2SO4. The endpoint is reached when 50.46 mL of the acid is mixed with the base. What is the molar concentration of the acid? I'm having a hard time even starting this problem, since I don't

    asked on May 24, 2007
  85. 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
  86. Physics

    A jet is circling an airport control tower at a distance of 23.0 km. An observer in the tower watches the jet cross in front of the moon. As seen from the tower, the moon subtends an angle of 9.49 10-3 radians. Find the distance traveled (in meters) by the

    asked on October 22, 2012
  87. physics

    On an air track, a 403.0 glider moving to the right at 2.30 collides elastically with a 501.0 glider moving in the opposite direction at 3.00 .Find the velocity of first glider after the collision

    asked on December 4, 2011
  88. Physics - PLease Help!

    A 38 cm length of wire has a mass of 6.0 g. It is stretched between two fixed supports and is under a tension of 145 N. What is the fundamental frequency of this wire?

    asked on January 26, 2010
  89. Chemistry II

    An unknown solute (a nonelectrolyte) was obtained and 5.37 g was weighed out. After dissolving the solute in water, the mass of the solution was 26.58 g. From the experimental results, the freezing point depression was found to be 3.6oC. If the freezing

    asked on September 8, 2009
  90. Astronomy

    If a space probe were sent into orbit around the sun that brought it as close as 0.5 AU to the sun and as far away as 5.5 AU, what would its orbital period be? Can I use Kepler's 3rd law for this? I'm not sure how to take into account both AUs...

    asked on March 17, 2008
  91. Physics

    A helicopter is flying in a straight line over a level field at a constant speed of 21.7 m/s and at a constant altitude of 11.5 m. A package is ejected horizontally from the helicopter with an initial speed of 21.6 m/s relative to the helicopter, and a

    asked on November 4, 2007
  92. 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? I need someone to check my work. I got about 3.797 as the inital velocity. I plugged this into

    asked on October 10, 2007
  93. 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
  94. Physics

    A model rocket is launched straight upward with an initial speed of 50 m/s. It accelerates with a constant upward acceleration of 2.00 m/s^2 until its engines stop at an altitude of 150 m. a) What is the max. height reached by the rocket? b) When does the

    asked on September 30, 2007
  95. 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
  96. Chemistry

    Icebergs in the North Atlantic present hazards to shipping, causing the length of shipping routes to increase by about 30 percent during the iceberg season. Attempts to destroy icebergs include planting explosives, bombing, torpedoing, shelling, ramming,

    asked on May 15, 2007
  97. Chemistry URGENT

    I have to match the items to the statements below, and I'm stuck! My answers are in parentheses, but I know that some of them are wrong. Please help if you know how...I would GREATLY appreciate it! A Dilute B Unsaturated C Saturated D Supersaturated 1.

    asked on April 24, 2007
  98. chemistry check

    1)A pocket of gas is discovered in a deep drilling operation. The gas has a temperature of 480c and is at a pressure of 12.8 atm. What volume of gas is required to provide 18.0 L of gas at the surface where the conditions are 22 C and 1.00 atm? is this

    asked on March 25, 2007
  99. Math

    These marbles are placed in a bag and two of them are randomly drawn. What is the probability of drawing 2 pink marbles if the first one is placed back in the bag before the second draw? There are 3 pinks, 2 yellows, and 5 blues.

    asked on October 13, 2015
  100. math

    these marbles are placed in a bag and two of them are randomly drawn what is the probability of drawing two pink marbles if the first one is placed back in the bag before the second draw the bag has 10 marbles.2 yellow.3 pink.5 blue

    asked on October 13, 2015


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