The walls of a refrigerator are constructed of a layer of fiberglass sandwiched between two panels of sheet metal. Assume the fiberglass is 50 mm thick and the thermal conductivity of the fiberglass is 0.046 W/(m-K). The steel panels have k = 60 W/(m-K) and are 3 mm thick. If the interior of the refrigerator is at 4 C at the exterior air is at 25 C determine the heat flux from the room into the refrigerator if the convection coefficients are h = 5 W/(m 2 -K) on both the interior and external surfaces of the sheet metal panels.