You are instructed to design a furnace wall capable of transmitting a maximum heat flux of 550W/m2. The inside and outside wall temperatures are to be maintained at 1100degC and 200degC, respectively. Two brick materials are available to line the walls of the furnace. Both have dimensions 22cm x 11cm x 7cm. One material has a thermal conductivity of 0,76W/mK, and a maximum usable temperature of 1300degC. Bricks are made of each material cost the same amount, and they laid in any manner. Determine the most economical arrangement of bricks.