54. a 4-m-high and 6-m-wide wall consists of a long 18-cm×30-cm cross section of horizontal bricks (k=0.72w/m°c) separated by 3-cm-thick plaster layers (k=0.22w/m°c). there are also 2-cm-thick plaster layers on each side of the wall, and a 2-cm-thick rigid foam (k=0.026w/m°c) on the inner side of the wall. the indoor and the outdoor temperatures are 22°c and -4°c, and the convection heat transfer coefficients on the inner and the outer sides are h1=10w/m^2°c and h2=20w/m^2°c, respectively. assuming onedimensional heat transfer and disregarding radiation, determine the rate of heat transfer through the wall.