Question

a man exerts 700 newtons of force to move a piece of furniture 4 meters. if it takes him 2 seconds to move the furniture how much power does it require

Answer 1

If he moves the piano 4 meters, with 700 newtons of force
in the direction of the motion, then the work done is

Work = (force) x (distance)

= (700 N) x (4 m) = 2,800 joules .

If he does all of that in 2 seconds, then
he did it at the rate of

(work) / (time) = (2,800 J) / (2 sec) = 1,400 watts

(about 1.88 'horsepower' !)