A fire in a room increases the interior wall surface temperature and maintains it at 800 C. The outside ambient air temperature is 20 C. If the wall is made of 200 mm brick, calculate the steady-state exterior wall surface temperature[C]. Write down your answer rounded to the nearest ones without any units. . Thermal conductivity of brick = 0.7 W/m-K . Convective heat transfer coefficient = 15 W/m2-K 168 142 240 254