At the gym, a man pulls a bar on a machine that works the muscles of the upper back. It takes him 0. 5 seconds to raise 30 kilograms of weights a vertical distance of 0. 5 meters.

Which of these exerts the same power output? (Estimate g as 10 m/s2. )

A) lifting 25 kilograms a distance of 2. 4 meters in 2. 0 seconds

B) lifting 45 kilograms a distance of 2. 4 meters in 3. 0 seconds

C) leg pressing 45 kilograms a distance of 0. 5 meters in 0. 5 seconds.

D) bench pressing 30 ligrograms a distance of 0. 5 meter in 1. 5 seconds.

Pleas help me