In Fig. $12.72,$ two identical, uniform, and frictionless spheres, cach of mass $m$, rest in a rigid rectangular container. A line connecting their centers is at $45^{\circ}$ to the horizontal. Find the magnitudes of the forces on the spheres from (a) the bottom of the container,
(b) the left side of the container,
(c) the right side of the container, and
(d) each other. (Hint: The force of one sphere on the other is directed along the center-center line.)