The gain in gravitational potential energy of the rock is 705.6 J.
Gravitational potential energy is the energy an object possesses due to its position in a gravitational field.
It is calculated as the product of the mass of the object (m), the acceleration due to gravity (g), and the change in height (h).
The formula is P.E. = mgh, where P.E. represents gravitational potential energy.
In this case, the 4.00 kg rock is raised 18.000 m.
To calculate the gain in gravitational potential energy, we use the formula: P.E. = (4.00 kg) * (9.8 m/s^2) * (18.000 m) = 705.6 J.