# Questions Asked onFebruary 24, 2012

1. ## Chemistry 101

if 95j of heat is added to a pure gold coin with a mass of 16 grams, what is its temperature change? Specific heat capacity of gold is 0.128 j/g degrees C.

2. ## physics

. An inquisitive physics student and mountain climber climbs a 50.0-m cliff that overhangs a calm pool of water. He throws two stones vertically downward, 1.00 s apart, and observes that they cause a single splash. The first stone has an initial speed of

3. ## statistics

A student scored 84 points on a test where the mean score was 79 and the standard deviation was 4. Find the student's z score, rounded to 2 decimal places

4. ## statistics

A scatter plot would be useful for A. Showing the relative number of sales of four different brands of blank DVDs B. Showing the trend of sales, over time, of five different brands of blank DVDs C. Showing the relationship between the sales of blank CDs

5. ## chemistry

Separate this redox reaction into its component half-reactions. O2 + 2Zn -->2ZnO

6. ## chemistry

a quantity of gas is collected over water at 15C. The manometer indicated a pressure of 24.0kPa. what would be the pressure of the dry gas?

7. ## physics

two charged bodies exert a force of 86N on each other. If they are moved so that they are 6 times farther apart, what is the new force that they will exert on each other?

8. ## chemistry

The quantity of antimony in a sample can be determined by an oxidation-reduction titration with an oxidizing agent. A 6.35-g sample of stibnite, an ore of antimony, is dissolved in hot, concentrated HCl(aq) and passed over a reducing agent so that all the

singular and plural pronouns direction revise each sentence. replace the underlined words with sigular or plural pronouns. 1- some people thought of a new sport, and the sport became popular. in this sentence the word underline is (the sport) my son write

10. ## chemistry

The reaction: A + 3 B = D + F was studied and the following mechanism was finally determined A + B = C (fast) C + B = D + E (slow) E + B = F (very fast) The step with largest activation energy is a. the first step b. the second step c. the third step d.

18. ## chemistry

For a certain chemical reaction, the rate constant at 250.0 °C is 0.00383 s-1 and the activation energy is 22.40 kilojoules. Calculate the value of the rate constant at 335.0 °C. a. 0.00513 s-1 b. 0.00946 s-1 c. 0.00787 s-1 d. 0.0224 s-1 e. 0.000640 s-1

168. ## math

The building is 16 by 12 feet so, to the nearest tenth of a foot what distance (x) fom the building should time place the 16-ft ladder so that the top of the ladder will be 12 feet above the ground?

169. ## math

antonio wants to buy a car that costs $2,500. he plans to put$400 down and pay the rest in six equal payments. find the amount of each payment

170. ## chemistryhelp

what does the electrolyte in batteries do?

171. ## physics

A 16.3 kg block is dragged over a rough, horizontal surface by a constant force of 157 N acting at an angle of 35 degree above the horizontal. Find the work done by the 157 N force.

172. ## Chemistry

A 300.0g sample of ice at -30.OC is mixed with 300.0G of water at 90C. Calculate the final temperature of the mixture assuming no heat loss to the surroundings. The heat capazities of H2O(s) and H20(L) are 2.03 and 4.18 j/g*C respectivly, and the entahply

173. ## physics

A rubber ball of mass 19.5 g is dropped from a height of 1.85 m onto a floor. The velocity of the ball is reversed by the collision with the floor, and the ball rebounds to a height of 1.55 m. What impulse was applied to the ball during the collision?

174. ## physics

A bowling ball weighing 43.0 N initially moves at a speed of 4.90 m/s. How long must a force of 51.0 N be applied to the ball to stop it?

175. ## math

. In the annual walkathon, Lee jogs for 5 3/4 miles more than he walks. If he travelled a total of 15 miles, how many miles did he walk?

176. ## algebra 1

(w^3-57w+43) / (w+8)

177. ## physics

A skater of mass 74.0 kg initially moves in a straight line at a speed of 4.60 m/s. The skater approaches a child of mass 45.0 kg, whom he lifts on his shoulders. Assuming there are no external horizontal forces, what is the skater's final velocity?

178. ## Math

This question is from my workbook (Pre-Calculus 11). Can someone please help me understand it? Suppose theta is an angle in standard position with terminal army in quadrant III and tan theta = 6/3. Determine the exact calues of the other two primary

180. ## TRIG/ALGEBRA

1) Find the exact value. Use a sum or difference identity. tan (-15 degrees) 2) Rewrite the following expression as a trigonometric function of a single angle measure. cos 3x cos 4x - sin 3x sine 4x

181. ## law

• What is the role of police in society? What would happen if the role of the police were lessened as it applies to the theory and practice of community policing?

182. ## World History

Around 700 B.C.,Athernians became unhappy with their form of government. What new type of government replaced it? A.aristocracy B.democracy C.oligarchy D.monarchy My answer is D ?

183. ## Physics - Newtons laws

A block (mass m1 = 8kg) is moving on an inclined plane, coefficient of kinetic friction of 0.45, whose angle is 30degrees. This block is connected to a second block (mass m2 = 22kg) by a cord that passes over a small frictionless pulley. Find the

184. ## Physics

What is energy