Two concentric conducting spherical shells each have a net charge of +1 C and all charges remain at rest. The outer shell has -2 C uniformly spread on its outer surface. How much charge is suspended within the central cavity (not touching the inner shell)? a) -4 C b) -3C c) -2C cl) -lC e)0C The inner surface of the inner shell is at a potential of 0 V. The inner surface of the outer shell may be at a potential of: a) -2 V b) 0 V c) +2 V d) more than one of the above answers could be correct e) none of the above answers may be correct