A conducting spherical shell of inner radius b and outer radius c is concentric with a small metal sphere of radius a < b. The metal sphere has a positive charge Q. The total charge on the conducting spherical shell is -Q. (Assume the potential is zero very far from all charges. Use a, b, c, k, and Q as necessary.)
(a) What is the electric potential of the spherical shell?
(b) What is the electric potential of the metal sphere?