1. The problem statement, all variables and given/known data A thick, spherical shell of inner radius a and outer radius b carries a uniform volume charge density ρ. Find an expression for the electric field strength in the region a<r<b. 2. Relevant equations Gauss's Law ∫E⋅dA Area of a sphere 3. The attempt at a solution I know I am really close to the answer, but I do not know what I am doing wrong. I know that there are two radii, but how do I find the electric field strength with these. I think I am close, but may be way off too. Can someone guide me to the way of solving this.