A small conducting spherical shell

A small conducting spherical shell with inner radius a and outer radius b is concentric with a larger conducting spherical shell with inner radius c and outer radius d. The inner shell has total charge +2q, and the outer shell has charge +4q.

a) Calculate the electric field E→(magnitude and direction) in terms of q and the distance r from the common center of the two shells for
(i) r < a;
(ii) a < r < b;
(iii) b < r < c;
(iv) c < r < d;
(v) r > d. Graph the radial component of E→ as a function of r.

b) What is the total charge on the
(i) inner surface of the small shell;
(ii) outer surface of the small shell;
(iii) inner surface of the large shell;
(iv) outer surface of the large shell?