A carpenter builds an exterior house wall with a layer of wood 2.9 cm thick on the outside and a layer of Styrofoam insulation 2.4 cm thick on the inside wall surface. The wood has k=0.080W/(mK), and the Styrofoam has k= 0.010 W/(mK). The interior surface temperature is 20.0 oC , and the exterior surface temperature is -15.0 oC .
a) What is the temperature at the plane where the wood meets the Styrofoam?
b) What is the rate of heat flow per square meter through this wall?