Set up triple integrals in spherical coordinates that compute the volumes of the following regions (do not evaluate the integrals):
a) the region A in the first octant bounded above by the sphere x^2 + y^2 + z^2 = 4
and below by the paraboloid x^2 + y^2 = 3z, and
b) the region B inside the sphere x^2 + y^2 + (z-5)^2 = 25