1. The problem statement, all variables and given/known data 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 (magnitude and direction) in termsof q and the distance r from the common center of the 2 shells fori) r<a; ii) a<r<b; iii) b<r<c; iv) c<r<d; v)r>d. b) what is the total charge on the i) inner surface of the smallshell; ii) outer surface of the small shell; iii) inner surface of the large shell; iv) outer surface of the large shell. 2. Relevant equations E.4πr^2=q/ε0 3. The attempt at a solution This is drawn in my textbook I have following doubts 1)why charge +4q is distributed /splitted in such a manner i.e +2q &+2q and then why one +2q is put in the circle of inner radius c and one +2q is placed in the circle of inner radius of d. 2)what is the difference between the positions p3 and p4 because my textbook states at P3 electric field would have some magnitude but at P4 electric field would be zero because it lies inside the conductor then why P3 is not considered to be inside the conductor?