11. Find the heat transfer per unit area through the composite wall in the figure. Assume onedimensional heat flow and there is no heat flow between B and C. The thermal conductivities are kA = 0.04W/m/oC, kB = 0.1W/mJoCkc = 0.03W/m/°C, and kD = 0.06W/m/oC.

r=370oC •

2.5cm-

A D Hi

'

7.5cm a^m, Area 0.1 m2

• r=66oc