A woman stands on the edge of a cliff and throws a stone vertically downward with an initial speed of 10 m/s. The instant before the stone hits the ground below, it has 450 J of kinetic energy. If she were to throw the stone horizontally outward from the cliff with the same initial speed of 10 m/s, how much kinetic energy would it have just before it hits the ground

It will have the same KE ( 450 J ) just before it hits the ground. The GPE transferred to KE is the same in both cases and the original KE is the same in both cases so the total will be the same.

The one thrown sideways will take longer to get to the ground but it will have the   same   velocity ( and therefore KE ) as the       thrown down stone.

Explanation:

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.