11. As shown in Fig. 6, an electrical hot plate inside a chamber generates heat in a rate of P = 100 W. One of the chamber walls is made of copper with thermal conductivity k_Cu = 401 W/m·K. The other walls are fiber wool which are nearly thermal insulated with k_fiber = 0.048 W/m·K. The copper wall thickness is 3 mm, and the cross-section area is 0.1 cm². If the temperature outside the chamber is T_L = 20 °C, in condition of thermal equilibrium, the temperature T_H inside the chamber is

(A) 24.8 °C
(B) 34.8 °C
(C) 58.8 °C
(D) 84.8 °C
(E) 94.8 °C