the walls of a house are 4 m high, 5 m wide, and 0.3 m thick. they are made from brick with thermal conductivity of 0.9 w/mk. the temperature of the air inside the house is 20 c and the outside air is at -10 c. there is a heat transfer coefficient of 10 w/m2k on the inside wall and 30 w/m2k on the outside wall. calculate the inside and outside wall temperatures, heat flux, and the total heat transfer rate through the wall.