The sphere of a Van de Graaff generator has a radius of 20 cm. The belt "pumps" charge into the sphere at a current of 0.22 ?A. Neglecting losses,
(a) what is the potential of the sphere after 10 seconds? What is the electric field
(b) inside the sphere,
(c) at the surface of the sphere, and
(d) 10 cm from the sphere?