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Que. Find the heat flow rate through the composite wall as shown in figure. Assume one dimensional flow and take

k 1 = 150 W/m degree
k 2 = 30 W/m degree
k 3 = 65 W/m degree
k 4 = 50 W/m degree
AB = 3 cm, BC = 8 cm and CD = 5 cm.
The distance between middle horizontal line from the top is 3 cm and from the bottom is 7 cm
a. 1173.88 W
b. 1273.88 W
c. 1373.88 W
d. 1473.88 W
Correct Answer:1273.88 W
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