A bowling ball (mass=72kg,Radius=0.11m) and A billiard ball (mass=0.47kg, Radius=0.028m)May each be treated as uniform sheres. What is the magnitude of the maximum gravitational force that each can exert on the other .

The maximum gravitational force occurs when they are in contact, i.e., as close together as possible. At that separation, the distance between the centers is
R = r1 + r2 = 0.128 m.

The maximum attractive force is
F = G* M1 * M2/R^2
where G is the universal constant of gravity. Look up G and compute that number.