A hollow spherical container has a wall made of a uniform solid material with thermal conductivity \(k\), inner radius \(r_1\), and outer radius \(r_2\). The inner surface is maintained at a constant high temperature \(T_H\), and the outer surface is maintained at a constant lower temperature \(T_C\). Thermal energy conducts radially outward through the wall under steady-state conditions at a constant total rate \(H\). Which of the following best describes a graph of the temperature \(T\) within the container wall as a function of radial distance \(r\) from \(r_1\) to \(r_2\)?