Consider a solid conducting sphere inside a hollow conducting sphere, with radii and charges specified in Problem 22.42. Take V = 0 as r→ ∞. Use the electric field calculated in Problem 22.42 to calculate the potential V at the following values of r:
(a) r = c (at the outer surface of the hollow sphere);
(b) r = b (at the inner surface of the hollow sphere);
(c) r = a (at the surface of the solid sphere);
(d) r = 0 (at the center of the solid sphere).