The use of drugs to treat disease is called medication
Im pretty sure that they do
The gravitational force will be one quarter.
The gravitational force between two objects is given by the formula
F=GMm/r^2
here, r is the distance between the objects.
Thus the gravitational force is inversely proportional to the square of the distance between the objects, Therefore if the distance between two objects is doubled the force will be one quarter.
My guess would be because the gravity from the Earth's core is constantly pulling the ball towards the ground. It's like the moon. Why doesn't the moon just float away in space? Because Earth's gravitational pull keeps it rotating around it. Therefore, the ball will always be pulled towards the core which keeps it from from rolling forever due to friction. But i may be wrong, even though this a quite a good answer, hope it is right!