A rustic cabin has a floor whose area is 3.50 m X 3.00 m. Its walls, which are 2.50 m high, are made of wood (thermal conductivity of 0.0600 W/m K) of 1.80 cm thickness and are apart with 1.50 cm of a synthetic material. when the temperature outside is 2.00 C, it is necessary to heat the room at a rate of 1.25 kW to maintain its temperature at 19.0 C. Calculate the thermal conductivity of the insulating material. Neglect heat loss through the ceiling and floor. Assume that the inner and outer surfaces of the wall have the same temperature as the air inside and outside the cabin