What is the weight, on earth, of a book with a mass of 1.5 kg

A2k pendulum has a speed of 1 m/s at a height of 1/2 meter

Astone weighing 1.5 kilograms is resting on a rock at a height of 20 meters above the ground. the stone rolls down 10 meters and comes to rest on a patch of moss. the gravitational potential energy of the stone on the moss is joules.

Which changes would result in a decrease in the gravitational force btween two objects? check all that apply