A solid sphere of +20C with radius a=1m. A conducting spherical shell of -30C with radius b=2m and c=3m is concentric with the solid sphere. 1. Find the inner and outer surface charge of the conducting spherical shell. My attempt: I just eyeballed it and said -20C is on the inner shell b/c the +20C is attracting it and the rest -10C is on the outer shell. 2. Graph V vs r(the radius from the center). My attempt: I calculated V at each of the regions. region 1: r<1 the V due to a solid sphere is (kQ/2R)(3-r^2/R^2)=30k-10r^2 region 2: 1<r<2 V=kQ/r=20k/r region 3: 2<r<3 r=0 region 4: r>3 V=-10k/r I attached my graph which i drew on paint. you can't see 0 between 2&3 but it's there.