Consider figure as a spherical dielectric shell so that = 0r for a < r < b

Consider figure as a spherical dielectric shell so that ε = ε0εr for a < r < b and ε = eo for 0 < r < a. If a charge Q is placed at the center of the shell, find
(a) P for a < r < b
(b) ρpv for a < r < b
(c) ρps at r = a and r = b