A flat plate solar collector, 6 ft by 12 ft, is mounted on the roof of a house. The outer surface of the collector is at 110 degree F and its emissivity is 0.9. The outside air is at 70 degree F and the sky has an effective temperature for radiation of 45 degree F. The collector transfers heat by natural convection to the air with a heat transfer coefficient of 3.2 Btu/h.ft2. degree F and also transfers heat by radiation to the sky. Calculate the total heat loss from the solar collector.