Questions Asked in 2006

Most Popular Questions of 2006

  1. Chemistry

    Hi. Is PO4(3-) polar or non-polar? Why or why not? Thanks! Look up the electronegativity of P and O. I think I remember that O is about 3.5 and P is about 2.1; therefore, each P-O bond is somewhat polar. Thus, the ion will be polar unless the Lewis

    asked by Sally on November 23, 2006
  2. Economics

    An industry currently has 100 firms, all of which have fixed costs of $16 and avg. variable cost as follows: Q Avg. Variable Cost ($) 1 1 2 2 3 3 4 4 5 5 6 6 a. Compute marginal cost and avg. total cost. b. the price is $10. what is the total quantity

    asked by Maggie on December 13, 2006
  3. Chemistry

    In a lab, we added NH3(aq) to CuSO4(aq), and the solution turned dark blue with a precipitate. The problem is that the products ( Cu(NH3)4 and SO4) should be soluble, no? The question is then, what is the percipitate? The ppt is Cu(OH)2. The dark blue

    asked by Karl on December 17, 2006
  4. Chemistry

    1) What Physical properties, other than specific heat, could you use to help identify unknown metals? 2) Why is water an excellent material to use in a calorimeter? Density, color, resistivity (or conductitivy), melting point, crystallization. 2) water is

    asked by K. on September 21, 2006
  5. finding c: calc

    let f(x)=square root x. if the rate of change of at x=c is twice its rate of change at x=1, then c=? what???? i don't get get it. to begin with, i took the derivative if that helps which is 1/(2*sqrtx) . f'(x) = 1/(2*sqrtx) is correct f'(x=1) = 1/2 The

    asked by david on December 5, 2006
  6. Chem 1

    It takes 208.4 kJ of energy to remove 1 mole of electrons from an atom on the surface of rubidium metal. What is the maximum wavelength (in nm) of light capable of removing a single electron from an atom on the surface of rubidium metal? Ok, I know I have

    asked by Rossi on October 21, 2006
  7. Economics

    you are hired as the consultant to a monopolistically competitive firm. The firm reports the following information about its price, marginal cost, and average total cost. Can the firm possibly be maximizing profit? If the firm is profit maximizing, is the

    asked by Sally on December 5, 2006
  8. Math

    If 5 fishermen catch 5 fish in 5 minutes, how many minutes will it take 50 fishermen to catch 50 fish? If 5 fishermen catch 5 fish in 5 minutes, then the average time it takes each fisherman is 5 minutes to catch one fish. It will take 50 fishermen 5

    asked by Sam on September 19, 2006
  9. physics

    Give two examples of ways that physicists model the physical world. I was wondering if this would be an effective answer for "give two examples of ways that physicists model the physical world." 1. Physicists build computer simulations. 2. They build

    asked by Anonymous on August 22, 2006
  10. Microeconomics - monopoly vs perfect competition

    This is a good and fun question that I am still scratching my head oever. We know monopoly's profit maximisation is MC=MR. We also know that perfect competition's profit maximising criteria is such that P=MC. Just what exactly does this mean? I know for

    asked by Sir Donsball on November 7, 2006
  11. physics

    THree blocks of masses 3m, 2m and m are connected to strings A,B, and C. The blocks are pulled along a rough surface by a force of magnitude F exerted by string C. The coefficient of friction between each block and the surface is the same. Which string

    asked by me on December 28, 2006
  12. Physic (concepts-please check my thoughts)

    A net torque applied to a rigid object always tends to produce? a)translational acceleration b) rotational equilibrium c) rotational acceleration d) rotational inertia e) none of these work (c) Torque produces torsion and tends to produce rotation. The net

    asked by Diane on December 10, 2006
  13. physics.

    A car travels forward with constant velocity. It goes over a small stone, which gets stuck in the groove of a tire. The initial acceleration of the stone, as it leaves the surface of the road is, a)vertically up b)horizontally forward c)horizontally

    asked by me on December 28, 2006
  14. Microeconomics

    Four roommates are planning to spend the weekend in their dorm room watching old movies, and they are debating how many to watch. Here is their willingness to pay for each film: Orson Alfred Woody Ingmar Frist film 7 5 3 2 Second film 6 4 2 1 Third film 5

    asked by Jeff on September 29, 2006
  15. MATH -BRAIN TEASER- PLEASE HELP

    page # D-76 What Relation Is a Doorstep to a Doormat? Both are stepped on. no You didn't put any parameters on this and I think its a great answer. How bout the relation being a stepson (steps on) I got astearther.... No wait it's A Step Farther eh....??

    asked by Adam on December 17, 2006
  16. physics

    A student holds one end of a string in a fixed position. A ball of mass .2 kg attached to the other end of the string moves in a horizontal circle of radius .5m with a constant speed of 5m/s. How much work is done on the ball by the string during each

    asked by me on December 28, 2006
  17. need help with 2 physics problems

    1. While following the directions on a treasure map, a pirate walks 45.0 m north, then turns and walks 7.5 m east. What single straight-line displacement could the pirate have taken to reach the treasure? 2. A hummingbird flies 1.2 m along a straight path

    asked by Anonymous on October 4, 2006
  18. MATH -BRAIN TEASER- PLEASE HELP

    Page # D-74 How Would You Describe a Dead Skunk? A skunked skunk. no What kind of answers do you have for the ones you have correct? exstankt extinct

    asked by Adam on December 17, 2006
  19. Probability

    A department store has determined that 25% of all their sales are credit sales. A random sample of 75 sales is selected and the proportion of credit sales in the sample is computed. a) What is the probability that the same proportion will be greater than

    asked by Janice on November 23, 2006
  20. chemistry

    Write out the net ionic equation for: Cd(NO3)2 + Na2S -----> 2NaNO3 + CdS ----- thanks!! Write out the net ionic equation for: Cd(NO3)2 + Na2S -----> 2NaNO3 + CdS If this is done in a water solution, then the sodium nitrate will be in solution, as was the

    asked by Tessa on September 12, 2006
  21. Calculus

    The line that is normal to the curve x^2=2xy-3y^2=0 at(1,1) intersects the curve at what other point? Please help. Thanks in advance. We have x2=2xy - 3y2 = 0 Are there supposed to be 2 equal signs in this expression or is it x2 + 2xy - 3y2 = 0 ? I'll

    asked by Jen on October 15, 2006
  22. english

    Who is the intended audience for the novel The Scarlet Letter? That is a good question. He wrote of historical times, of sin, guilt, and repentance. He wrote of social mores, social pressure, and the pain of reconciling this with personal morals. I think

    asked by anonymous on October 26, 2006
  23. Physics

    A 50.0 g silver spoon at 20.0 degrees Celsius is placed in a cup of coffee at 90.0 degrees C. How much heat does the spoon absorb from the coffee to reach a temp. of 89.0 degrees C? Rememeber this equation. It, or a slight modification of it, will work all

    asked by Erica on November 21, 2006
  24. Chemical Formulas and Reactions

    When aqueous copper(II)chloride reacts with aqueous ammonium phosphate, soluble ammonium chloride forms and copper(II) phosphate precipitates out of solution. 1. Write the balanced molecular equationfor this reaction. 2. Write the balanced complete ionic

    asked by chrissy on December 29, 2006
  25. physics

    Identify the area of physics that is most relevant to each of the following situations. Explain your reasoning. a. a high school football game b. food preperation for the prom c. playing in the school band d. lightning in a thunderstorm e. wearing a pair

    asked by Anonymous on August 21, 2006
  26. calc help showed work

    If the function f has a continuous derivative on [0,c], the the integral(o to c) of f'(x)dx= a)f(c)-f(0) b)absolute value (f(c)- f(0)) c) f(c) d)f'(x)=c e)f"(c)-f"(0) My work: so the the answer to the integral is f(x) and when find the answer from o t0 c,

    asked by david on December 7, 2006
  27. Probability

    A salesperson contacts eight potential customers per day. From past experience, we know that the probability of a potentail customer making a purchase is 0.10. a) What is the probability the salesperson will make at least two sales in a day? -Do you use

    asked by Janice on November 23, 2006
  28. economics

    Suppose that people consume only three goods, as shown in this table: (5 Marks) Tennis Balls Tennis Racquets Gatorade 1998 price $2 $40 $1 1998 quantity 100 10 200 1999 price $2 $60 $2 1999 quantity 100 10 200 What is the percentage change in the price of

    asked by shelby on September 25, 2006
  29. Chemistry!

    When 2.5g of NaOH were dissolved in 49.0g water in a calorimeter at 24.0 C, the temperature of the solution went up to 37.1 C. a. Is the solution reaction exothermic? Why? The temperature or the water went from 24.0 to 37.1 which is an increase. If the

    asked by DrBob222 on December 4, 2006
  30. Chemistry

    Can you please answer this question: Both water and carbon dioxide are triatomic molecules. Explain why one of these molecules is polar and the other is nonpolar? Carbon dioxide is linear :C::O::C: and therefore has no net electrical dipole. Water is a

    asked by Beautiful on December 16, 2006
  31. Same substances?

    Question: Two substances, A and B, have the same melting point. how can you determine if they are the same without using any form of spectroscopy? Explain in detail. My answer: Perform a mixture melting point. In this procedure, pulverize and mix A and B

    asked by Sheryl on October 1, 2006
  32. physics

    You throw a ball toward a wall with a speed of 25m/s and at an angleof 40 degree above the horizontal. The wall is 22m from the realease point of the ball. a) How far above the release point does the ball hit the wall? b) What are the horizontal and

    asked by Bobby on October 25, 2006
  33. Math

    The Garraty company has two bond issues outstanding. Both bonds pa $100 annual interest plus $1,000 at maturity. Bond L has a maturity of 15 years and Bond S a maturity of 1 year. A). What will be the value of each of these bonds when the going rate of

    asked by Dee Dee on June 17, 2006
  34. Linear Approximation

    Use linear approximation, i.e. the tangent line, to approximate 1/0.104 as follows: Let f(x)=1/x and find the equation of the tangent line to f(x) at a "nice" point near 0.104 . Then use this to approximate 1/0.104 . L(x)=f(a)+f'(a)(x-a)...i think. You're

    asked by Jojo on October 14, 2006
  35. chemistry

    Asprin, C9H8O4, is prepared by reacting salicylic acid, C7H6O3, with acetic anhydride, C4H6O3, in the reaction C7H6O3(s) + C4H6O3(l) -> C9H8O4(s) + C2H4O2(l) A student is told to prepare 45.0 g of aspirin. She is also told to use a 55.0% excess of the

    asked by Chris on October 18, 2006
  36. Economics

    Suppose the price elasticity of demand for heating oil is 0.2 in the short run and 0.7 in the long run. c. If the price of heating oil rises from $1.80 to $2.20 per gallon, what happens to the quantity of heating oil demanded in the short run? In the long

    asked by Jon on October 6, 2006
  37. Microeconomics

    Larry, Moe, and Jo run the only saloon in town. Larry wants to sell as many drinks as possible without losing money. Jo wants the saloon to bring in as much revenue as possible. Moe wamts to make the largest possible profits. Using a single diagram of the

    asked by Alex on December 8, 2006
  38. Chemistry

    Compounds like CCL2F2 are known as chloroflourocarbons, or CFCs. These compounds were once widely used as refrigerants but are now being replaced by compounds that are believed to be less harmful to the environment. The heat of vaporization of CCl2F2 is

    asked by Jenn on December 14, 2006
  39. Math Riddle

    What day would yesterday be if Wednesday was five days before the day after tomorrow? pLEASE HELP ME WITH THE RIDDLE i POSTED!!!!!! EARLIER waht materials could upumuse Alright already! I really wondered why you just didn't pick up a calendar and work the

    asked by Angel67 on August 30, 2006
  40. Physics

    A small first-aid kit is dropped by a rock climber who is descending steadily at 1.9 m/s. After 2.5 s, what is the velocity of the first-aid kit, and how far is the kit below the climber? My question is, how can you determine how fast/far the kit is

    asked by Help again?? Becca on September 17, 2006
  41. English 2

    I have to do a 1000 word essay paper detailing the research of a career that is of interest to me.I picked a teacher but cant find any info on it. I have to get things like salary scale, retirement plans,daily duties,typical hours worked,types of training

    asked by Tim on December 3, 2006
  42. Chemistry

    Which element listed should have chemical properties similar to fluorine (F) A.Li B.Si C.Br D.Ne Br, along with F, a halogen (column 7 of the periodic table) Look at the periodic table. The columns are called groups. Elements in the same group have similar

    asked by Brian on November 9, 2006
  43. english

    I woul like to review my essay please? Post it. Can you please help me write that essay" A way to decrease your chance of becoming a victim of random ciolence". Hmmm. You have an assignment to write an essay, a teacher offers to review your essay, and you

    asked by louise on November 30, 2006
  44. Low recovery

    The question is: A student performs a crystallization on an impure sample of biphenyl. The sample weighs 0.5g and contains about 5% impurity. Using his knowledge of solubility, he decides to use benzene as a solvent. The final weight is only 0.02g. Why is

    asked by Sheryl on September 26, 2006
  45. Concentration increase

    Question: What would happen to the Rf values of the pigments if you were to increase the relative concntration of acetone in the developing solvent? Note: The development solvent used was 70% hexane - 30% acetone. My answer: Acetone is more polar than

    asked by Sheryl on October 22, 2006
  46. The lord of the flies-English

    Why is percival unable to remember his name and address? Please help!! :( He is one of the "littleuns". He is so traumatized by the events he lives through that he forgets what civilization is about, including his name.

    asked by Help! on December 3, 2006
  47. physics: scalars/vectors

    Please check. 1. Which of the following quantities are scalars, and which are vectors? a. the acceleration of a plane as it takes off- VECTOR b. the number of passengers on the plane- SCALAR c. the duration of the flight- SCALAR d. the displacement of the

    asked by Anonymous on September 17, 2006
  48. Pre-Calculus

    The formula D= 5e ^-0.4h can be used to find the number of milligrams D of a certain drug that is in a patient's bloodstream h hours after the drug has been administered. When the number of milligrams reaches 2, the drug is to be administered again. WHat

    asked by Erica on October 10, 2006
  49. calculus

    If y is a differentiable function of x, then the slope of the tangent to the curve xy - 2y + 4y^2 = 6 at the point where y=1 is ...... How do I do this? Thanks. xy - 2y + 4y^2 = 6 ---> d[xy - 2y + 4y^2] = 0 ---> xdy + ydx - 2dy + 8ydy = 0 ---> (x + 8y -

    asked by Jen on December 3, 2006
  50. Probaility

    The rates of on time flights for commercial jets are continuously tracked by the US Department of Transportation. Recently, Southwest Air had the best rate of 80% of its flight time on time. A test is conducted by randomly selecting 15 southwest flights

    asked by Mary on December 5, 2006
  51. Law of Multiple Proportions

    Two elements, R and Q, combine to form two binary compounds. In the first compound, 14.0 g of R combines with 3.00 g of Q. In the second compound, 7.00 g of R combines with 4.50 g of Q. Show that these data are in accord with he law of multiple

    asked by Shell on November 14, 2006
  52. Calculus, AntiDerivatives

    I need help with this problem: A car traveling at 43 ft/sec decelerates at a constant 5 ft per second squared. How many feet does the car travel before coming to a complete stop? I'm not sure where to start, i know how to find antiDerivatives, but i don't

    asked by Mike on November 23, 2006
  53. ap chemistry

    Discuss briefly the relationship between the dipole moment of a molecule and the polar character of the bonds within it. WIth this as a basis, account for the difference between the dipole moments of CH2F2 and CF4. does anyone have any idea? the greater

    asked by someone on December 7, 2006
  54. PHYSICS PLEASE HELP QUICK

    An object with an initial speed of 4.0 meters per second accelerates uniformly at 2.0 meters per second2 in the direction of its motion for a distance of 5.0 meters. What is the final speed of the object? Vi=4m/s a=2.0m/s*s d=5.0m Vf=? Vf©÷=Vi©÷+2ad

    asked by Katelyn on October 5, 2006
  55. Chem - Elements

    I need help on identifying four elements. 1. a member of the same family as oxygen whose most stable ion contains 54 electrons. (Sulfur?) 2. member of alkali metal family whose most stable ion contains 36 electrons. (Cesium??) 3. noble gas with 18 protons

    asked by Salil on November 14, 2006
  56. PHYSICS HELP

    A 525-N trunk is placed on an inclined plane that forms an angle of 30.0 degrees with the horizontal. What are the components of the weight parallel to the plane and normal to the plane? Memorize this: weight normal = mg cosTheta weight parallel= mg Sin

    asked by Suzanne on October 16, 2006
  57. calc

    the volume of a cylindrical tin can with a top and a bottom is to be 16*pi cubic inces. if a minimum amont of tin is to be used to construct the can, what must be the height, in inches, of the can? volume of cyliner is pi*r^2*h do i like take derivitive of

    asked by david on December 8, 2006
  58. physics

    A 10 kg monkey climbs up a massless rope that runs over a frictionless tree limv and back down to a 15kg package on the ground. a) what is the magnitude of the least acceleration the monkey muct have if it is to ligt the package off the ground? If after

    asked by Bri on November 21, 2006
  59. TLC purity

    Question: A student spots an unknown sample on a TLC plate and develops it in dichloromethane solvent. Only one spot, for which the Rf value is 0.95, is observed. Does this indicate that the unknown material is a pure compound? What can be done to verify

    asked by Sheryl on October 13, 2006
  60. Chemistry

    My question is basically to find out what these reactants yield: CuCl2(aq) + NH3(aq) --> ? my best guess here is... CuCl2(aq) + 6NH3(aq)-->[Cu(NH3)4(H2O)2]2+ + N2(g) + 2HCl Im pretty sure about the [Cu(NH3)4(H2O)2]+2 part but not sure about the rest. The

    asked by Frederique on November 7, 2006
  61. phyiscs

    How do I do these? Draw a free-body diagram for each of the following objects? a. a projectile in motion in the presence of air resistance b. a rocket leaving the launch pad with its engines operating c. a heavy crate being pushed across a rough surface a.

    asked by Anonymous on December 5, 2006
  62. Physics

    A baseball thrown at an angle of 55.0 degrees above the horizontal strikes a building 16.0 m away at a point 8.00 m above the point from which it is thrown. Ignore air resistance. Find the magnitude of the initial velocity of the baseball (the velocity

    asked by Julie on September 19, 2006
  63. discrete math

    list five integers that are congruent to 4 modulo 12 4, 16, 36, ... any integer of the from n*12 + 4 where n=0, 1, 2, 3...

    asked by thisha on November 6, 2006
  64. history

    Why, when, and where did Abraham Lincoln say "What kills a skunk is the publicity it gives itself." ? Thanks. Since this is not my area of expertise, I searched Google under the key words "Abraham Lincoln Skunk quote" to get possible sources. I got over 15

    asked by April on October 15, 2006
  65. PHYSICS

    A car is traveling 27 m/s when the driver sees a child standing in the road. He takes 0.8 s to react, then steps on the brakes and slows at 8.0 m/s2. How far does the car go before it stops? please help!! Since he's going 27 m/s, and he takes 0.8 s to

    asked by Katelyn on September 26, 2006
  66. Mobility and Rf

    We did a column chromatography then a TLC on extracted spinach pigments. Question: Why are the chlorophylls less mobile on column chromatography and why do they have lower Rf values than the carotenes? My answer: The chlorophylls are more polar than the

    asked by Sheryl on October 22, 2006
  67. physics

    A student is testing the kinematic equations for uniformly accelerated motion by measuring the time it takes for light-weight plastic balls to fall to the floor from a height of 3 m in the lab. The student predicts the time to fall using g as 9.8 m/s^2 but

    asked by me on December 28, 2006
  68. science

    sometimes scientists make a mistake, or ?, and need to do an experiment again or the data is not as expected, and need....

    asked by chris on October 10, 2006
  69. Calc

    A car traveling at 43 ft/sec decelerates at a constant 5 feet per second squared. How many feet does the car travel before coming to a complete stop? i tried a few different equations, none of the worked. 43t - 5t^2 = 0 43 - 10t = 0 21.5t^2 - (5/3)t^3 = 0

    asked by Norris on November 23, 2006
  70. Social Studies!

    2.) What is the name of the landform north of 40 degrees north latitude that juts out into the Atlantic like a giant fishhook? 3.) What flatlands extend south from the Cheapsake Bay to the east coast of Florida? 4.) From the top of which mountain range in

    asked by becca on September 9, 2006
  71. Drug Abuse and Addiction

    I need research sources for drug abuse and addiction. Thank you. Check these sources -- http://www.nida.nih.gov/ http://teens.drugabuse.gov/ (Broken Link Removed) http://www.drugabusestatistics.samhsa.gov/

    asked by Brian on November 12, 2006
  72. Physics

    A sphere of mass 3.0X10^-4 kg is suspended from a cord. A steady horizontal breeze pushes the sphere so that the cord makes a constant angle of 37 degrees with the vertical. find a) the magnitude of that push and b) the tension of the cord. I looked

    asked by Amy on November 12, 2006
  73. Physics

    A stunt pilot of mass 55.0 kg who has been diving her airplane vertically pulls out of the dive by changing her course to a circle in a vertical plane. A)If the plane's speed at the lowest point of the circle is 95.6 m/s , what is the minimum radius of the

    asked by Kuwaiti on November 14, 2006
  74. biology

    What connections can you identify between the metric units for length and volume length x length x length = cubic length. That is cm x cm x cm = cubic centimeters or m x m x m = cubic meters. That is length used to measure the sides will provide a volume.

    asked by wow on September 25, 2006
  75. physics

    A student sits on a freely rotating stool holding two weights, each of which has a mass of 3.00 kg. When his arms are extended horizontally, the weights are 1.00 m from the axis of rotation and he rotates with an angular speed of 0.750 rad/s. The moment of

    asked by nicole on December 5, 2006
  76. Last physics help question (my thoughts given)

    A 160-N child sits on a light swing and is pulled back and held with a horizontal force of 100N. The tension force of each of the two supporting ropes is: a) 60N b) 94N c) 120N d) 190N e) 260N work: weight is down, the pull is back, so the tension must act

    asked by diane on December 11, 2006
  77. Physics

    A 50.0 kg parachutist jumps out of an airplane at a height of 1.00 km. The parachute opens, and the jumper lands on the ground with a speed of 5.00 m/s. By what amount was the jumper's mechanical energy reduced due to air resistance during this jump? so,

    asked by Becca on December 5, 2006
  78. Physics

    An athlete starts at point A and runs at a constant speed of 5.40 m/s around a round track 250 m in diameter. Find the x component of this runner's average velocity between points A and B. (answer is 3.44 m/s) Find the y component of this runner's average

    asked by Josh on September 13, 2006
  79. physics

    An 8.0 g bullet is fired horizontally into a 9 kg block of wood and sticks in it.The block,which is free to move,has a velocity of 40cm/s after impact.Find the initial velocity of a bullet. You know the momentum (total mass) of the bullet/block combo after

    asked by fluffy on September 23, 2006
  80. Chemistry

    You made 100.0 ml of a lead (II) nitrate solution for lab but forgot to cap it. The next lab session you noticed that there was only 80.0 ml left. In addition, you forgot the initial concentration of the solution. You decide to take 2.00 ml of the solution

    asked by Anonymous on October 30, 2006
  81. Physics help--explosion

    Figure 9-56 shows a two-ended "rocket" that is initially stationary on a frictionless floor, with its center at the origin of an x axis. The rocket consists of a central block C (of mass M = 6.00 kg) and blocks L and R (each of mass m = 2.90 kg) on the

    asked by fizzix on December 2, 2006
  82. science

    name a chemical sometimes used to make the specimen visible on a microscope. answer needs to be 5 leters stain thank you tell me an example of solidification.. please :) When water, a liquid, freezes to a solid, ice. Also called crystallization. stage

    asked by jenna on September 8, 2006
  83. Economics

    3. Suppose the Clean Springs Water Company has a monopoly on bottled water sales in California. If the price of tap water increases, what is the change in Clean Springs' profit-maximizing level of output, price, and profit? Explain in words and with a

    asked by Mariah on December 3, 2006
  84. Phase diagram

    Question: A solid substance has a vapor pressure of 800 mm Hg at its melting point (80 degrees C). Describe how the solid behaves as temperature is raised from room temperature to 80 C while the atmospheric pressure is held constant at 760 mm Hg. I think

    asked by Sheryl on November 12, 2006
  85. d/dx

    d/dx( ln |sin(pi/x)| ) = ? Thanks. If those are absolute value signs, the derivative will not exist when sin (pi/x) = 0, because of the sign change that occurs there. Assume sin (pi/x) > 0 Let u(x) = pi/x and v(x) = sin x, and use the chain rule. d/dx ln

    asked by Jen on December 13, 2006
  86. Econ.

    In recent years, some policymakers have proposed requiring firms to give workers certain fringe benefits. For example, in 1993, President Clinton proposed requiring firms to provide health insurance to their workers. Let’s consider the effects of such a

    asked by Jenny on December 4, 2006
  87. PHYSICS

    A 2.00 METER TALL BASKETBALL PLAYER ATTEMPTS A GOAL 10.00 METERS FROM THE BASKET(3.05 METERS HIGH). IF HE SHOOTS THE BALL AT A 45.0 DEGREE ANGLE, AT WHAT INITIAL SPEED MUST HE THROW THE BALL SO THAT IS GOES THROUGH THE HOOP WITHOUT STRIKING THE BACKBOARD?

    asked by Jill Hefner on November 1, 2006
  88. science

    Written out, would the reaction between anihiline [C6H5NH2] and perchloric acid look like this: C6H5NH2 + HClO4 -> C6H5ClO4 + HNH2 ? The NH2 group on aniline is basic. It takes on a H^+ from HClO4 and forms the salt. The salt is C6H5NH3^+ + ClO4^-. I hope

    asked by Crystal on October 19, 2006
  89. Sample purity

    Question: A student spots an unknown sample on a TLC plate and develops it in pentane solvent. Only one spot, for which the Rf value is 0.05, is observed. Is the unknown a pure compound? What can be done to verify the purity of the sample using TLC? My

    asked by Sheryl on October 15, 2006
  90. Physics

    A box of textbooks of mass 25.3 kg rests on a loading ramp that makes an angle (ALFA) with the horizontal. The coefficient of kinetic friction is 0.260 and the coefficient of static friction is 0.330 . A) As the angle (ALFA) is increased, find the minimum

    asked by Jasijo on November 18, 2006
  91. math/unit rate

    please help me find the definition for unit rate. It depends upon what kind of unit. Go to www.google.com and type in unit rate. There is one source there for hotel unit rates, another for unit rates for the medical field, etc. You may also go to

    asked by hannah on September 26, 2006
  92. Mixed melting point

    Question: A compound melting at 134 degrees C was suspected to be either aspirin (mp 135C) or urea (mp 133C) Explain how you could determine whether one of these two suspected compounds was identical to the unknown compound without using any form of

    asked by Sheryl on October 1, 2006
  93. Economics

    6. Show the effect of each of the following events on the market for labor in the computer manufacturing industry. Use graphs. a. Congress buys personal computers for all American college students. Wouldn't the demand curve shift to the right while the

    asked by Mariah on December 4, 2006
  94. physics

    A red train traveling at 72 km/h and a green train traveling at 144 km/h are headed toward one another along a straight, level track. When they are 950m apart, each engineer sees the other’s train and applies the brakes. The brakes decelerate each train

    asked by jenny on September 18, 2006
  95. Physics

    A river flows due south with a speed of 2.00 m/s. A man steers a motorboat across the river; his velocity relative to the water is 4.20 m/s due east. The river is 800 m wide. What is the magnitude of his velocity relative to the earth? got it....4.65 m/s

    asked by Josh on September 16, 2006
  96. Biology

    Evaluate the difficulties with reintroduction programs using captive-born animals. thanks, Amber I have no idea

    asked by Amber on October 17, 2006
  97. Social Studies

    What is the real difference between 'Social Studies' and History? History is one branch of social studies. In high school, they often amount to the same thing, but "social studies" seems to be supplanting the teaching of chronolgical history. Other

    asked by Julie L. on August 20, 2006
  98. Rf values

    Question: Consider a sample that is a mixture composed of biphenyl, benzoic acid and benzyl alcohol. The sample is spotted on a TLC plate and developed in a dichloromethane-cyclobutane solvent mixture. Predict the relative Rf values for the three

    asked by Sheryl on October 14, 2006
  99. Watershed?

    What parts of the environment, natural and manmade, make up a watershed? Watersheds aren't really important to humans in and of themselves, it is the amount of precipitation what is caught up within the watershed. Look at Brazil in an atlas. The Amazon has

    asked by Anonymous on November 1, 2006
  100. Biology

    Describe two practical applications for being able to extract DNA from cells. Genetically engineering insulin producing bacteria Crime lab testing of blood (white cells have DNA) and semen what are some biome characteristics for a freshwater wetland

    asked by Anonymous on October 5, 2006