Given
m: mass
m = 78kg
h: height
h = 15m
t: time
t = 18s
Procedure
Power is a physical concept with several different meanings, depending on the context and the available information. We can define power as the rate of doing work, and it is the amount of energy consumed per unit of time.
First, we need to calculate the work done, which requires the force necessary to lift the box against gravity:
The power is
The power would be 637 W