Determine the temperature at the cartridge heater embedded in a perfectly conductive material on the inner surface of a 0.1 m thick aluminum wall (thermal conductivity k = 200 W/m·K, area A = 1 m^2). The cartridge heater provides a steady-state heat flux of 20000 W/m^2 through the wall via conduction. The outer surface of the wall is in perfect thermal contact with a consumable cartridge, which is maintained at a constant temperature of 30°C to facilitate a heating process. Ignore radiation effects. What is the temperature at the cartridge heater (inner surface of the wall)?