How much heat is lost due to convection in a 25-min period from a 52 ft × 14-ft wall, if the difference between the wall temperature and the air temperature is 54°F and the surface of the wall has a...

How much heat is lost due to convection in a 25-min period from a 52 ft × 14-ft wall, if the difference between the wall temperature and the air temperature is 54°F and the surface of the wall has a heat transfer ratio of 0.17 BTU/h ft2 °F?