3. A 4m high and 6m wide wall consists of a long 18cm30cm cross section of horizontal bricks (k=0.65W/m.K) separated by 3cm thick plaster layers (k=0.15W/m.K). There are also 2cm thick plaster layers on each side of the wall and a 2cm thick rigid foam (k=0.016W/m.K) on the inner side of the wall. The indoor and outdoor temperatures are 25 and 10C, respectively. Convection heat transfer coefficients on the inner and outer sides are 15W/m2.K and 25 W/m2.K, respectively. Assuming one dimensional heat transfer and ignoring radiation, determine the rate of heat transfer through the wall