contestada

A 1.30 kg ball is attached to a ceiling by a
1.93 m long string. The height of the room is
3.41 m.
The acceleration of gravity is 9.81 m/s^2.
What is the gravitational potential energy
associated with the ball relative to
a) the ceiling?
b.)the floor?
c.)a point at the same elevation as the ball?
(answer in J)