A spherical shell of inner and outer radii r_i and r₀, respectively, is filled with a heat-generating material that provides for a uniform volumetric generation rate (W/m³) of q. The outer surface of the shell is exposed to a fluid having a temperature T_∞ and a convection coefficient h. Obtain an expression for the steady-state temperature distribution T(r) in the shell, expressing your result in terms of r_i, r₀, q, h, T_∞, and the thermal conductivity k of the shell material.