Answer:
400 J
Step-by-step explanation:
Work is done when a force that is applied to an object moves that object.
The work is calculated by multiplying the force by the amount of movement of an object
W = F * d
here the man has to work against the gravitational field. (against his weight)
F =100 N
Work done = F * d
= 100 * 4
= 400 J