A nonconducting sphere of radius r0 carries a total charge Q distributed uniformly throughout its volume.

Part A: Determine the electric potential as a function of the distance r from the center of the sphere for r>r0. Take V=0 at r=?.
Part B: Determine the electric potential as a function of the distance r from the center of the sphere for r Express your answer in terms of some or all of the variables r0, Q, r, and appropriate constants.