Philosophy homework help

A carpenter builds an exterior house wall with a layer of wood 3.2cm thick on the outside and a layer of Styrofoam insulation 2.3 cm thick on the inside wall surface. The wood has k=0.080W/(m?K), and the Styrofoam has k= 0.010 W/(m?K). The interior surface temperature is 20.0 ?C , and the exterior surface temperature is -11.0 ?C .What is the temperature at the plane where the wood meets the Styrofoam?Express your answer using two significant figures.