Please answer in as much detail as possible.

1. (25 points) A furnace wall consists of 100 mm of brick A, 20 mm brick B, and 10 mm of steel plate. Temperature at the fire side is at 1200 C, and temperature of outside is at 30 C. A chemical engineer found that the heat loss from the wall is 500 W/m and he found a thin layer between brick B and steel plate. Estimate the thickness (in mm) of the air layer assuming that the thermal conductivity of the air layer is equivalent to that of brick B. (ka=2.0 W/mC, kB=0.2 W/mC, ksp=45 W/mC) 1) Draw the wall 2) Derive the equations for q and thermal resistances of each layer. 3) The thickness of the air layer in mm? 4) The interface temperature between bricks A and B in C