All spheres in this problem have radius a, constant density k, and mass in. Find in terms

Question:

All spheres in this problem have radius a, constant density k, and mass in. Find in terms of ( and m the moment of inertia of each of the following:
(a) A solid sphere about a diameter
(b) A solid sphere about a tangent line to its boundary
(c) The two-sphere solid of Figure 10 about the z-axis