1. A 3-m-high and 6-m-long wall is constructed of two large plates of material A separated by 1- cm-thick and 20-cm-wide steel plates (k = 15.1 W/m-C) placed 50 cm apart. The remaining space between the steel plates is filled with material B. If the inner side of the room is 28C and the temperature outside the room is 3C. The convection heat transfer coefficient inside and outside the room is given as 5 W/m.C and 12 W/m.C, respectively. a. Draw the thermal resistance network for the wall. b. Considering that the house is losing 15 kW during winter, suggest a combination of the wall materials (A and B) and the thickness (L) so that the design achieves an insulation effect. Surrounding, 3C Steel Room, 28C A B A 50 cm Steel 1 cm L cm 10L cm L cm (10 marks)