The potential at the surface of a sphere (radius R) is given by V0 = k cos 3, where k is a constant. Find the

The potential at the surface of a sphere (radius R) is given by V0 = k cos 3θ, where k is a constant. Find the potential inside and outside the sphere, as well as the surface charge density σ (θ) on the sphere. (Assume there's no charge inside or outside the sphere.)