$2.$ A spherical conducting shell of inner radius b and outer radius c encloses a solid sphere with radius a and charge density $.$ Use Gauss$$ Law to find the electric field at points r from the center of the sphere. $=0\mathrm{.}23$ a$)$ r $<$ a r $=8$ cm a $=10$ cm b$)$ a $<$ r $<$ b r $=13$ cm b $=15$ cm c$)$ b $<$ r $<$ c r $=18$ cm c $=20$ cm d$)$ r $>$ c r $=25$ cm e$)$ Use Gauss$$ Law to find the charge on the inside surface of the shell? on the outside surface $?$ explain your reasoning.