A concrete wall is 15.0 cm thick and has an area of 10.0 m2. A layer of wood that is 2.50 cm thick is placed over the wall to reduce the loss of heat by thermal conduction. The coefficient thermal conductivity of concrete is 1.70 W/m 
and the coefficient of thermal conductivity of wood is 0.0400 W/m 
What is the effective coefficient of thermal conductivity of the wood on concrete system?
A. 0.245 W/m 
B. 1.22 W/m
C. 1.65 W/m
D. 2.02 W/m
E. 2.34 W/m
A. 0.245 W/m
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