QUESTION 9 A thick conducting spherical shell with inner radius a and outer radius b is surrounded by a concentric thick conducting shell with inner radius c and outer radius d. There is a point charge at the center of the spheres (black dot) with charge +3.00 C. The smaller shell has excess charge +2.00 C and the outer shell has excess charge -7.00 0 . (. = 8.85 x 10-12 m 2INC?) What is the surface charge density on the outer surface of the larger shell (radius d) if d = 0.500 m? (Give the numerical value only, using units of C/m-) a b d