Answer:
U = 66,150 J
Step-by-step explanation:
Gravitational Potential Energy
Gravitational potential energy is the energy stored in an object because of its vertical position or height in a gravitational field.
It can be calculated with the equation:
U=m.g.h
Where m is the mass of the object, h is the height with respect to a fixed reference, and g is the acceleration of gravity or
.
The child of mass m=45 Kg is perched above a h=150 m ravine. His gravitational potential energy is:

U = 66,150 J