(Target E3) A solid sphere made of nonconducting material is suspended by a thin thread (also nonconducting) inside a hollow sphere made of a conductor. The solid sphere has a radius a and the conducting sphere has a radius b. The solid sphere has a volume charge density given by \rho(r)=\rho_{0}\left(\frac{a}{r+a}\right) where po is a constant, and r is the distance from the center of the sphere. The conducting shell has uniform surface charge density a. (b) Determine the electric field in the region r b