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' !)