Fleas have remarkable jumping ability. a 0.45 mg flea, jumping straight up, would reach a height of 30 cm if there were no air resistance. in reality, air resistance limits the height to 20 cm .
part a what is the flea's kinetic energy as it leaves the ground?
part b at its highest point, what fraction of the initial kinetic energy has been converted to potential energy? express your answer using two significant figures.

An insurance company wants to know if the average speed at which men drive cars is higher than that of women drivers. the company took a random sample of 27 cars driven by men on a highway and found the mean speed to be 72 miles per hour with a standard deviation of 2.2 miles per hour. another sample of 18 cars driven by women on the same highway gave a mean speed of 68 miles per hour with a standard deviation of 2.5 miles per hour. assume that the speeds at which all men and all women drive cars on this highway are both approximately normally distributed with unknown and unequal population standard deviations.

What happens to atoms and chemical bonds during a reaction?

Imagine you had to physically add electrons, one at a time, to a previously neutral conductor. you add one electron very easily, but the second electron requires more work. in your initial post to the discussion, explain why this is. also, what happens to the work needed to add the third, fourth, fifth, and subsequent electrons