3. (4 points). A house has a composite wall of wood, fiberglass insulation, and plaster board, as indicated in the sketch. On a cold winter day, the convection heat transfer coefficients are ho =60 W/m². K and h₁ = 30 W/m².K. The total wall surface area is 350 m².**Given: Fiberglass blanket: k₁ = 0.038 W/m.K Plywood siding: ks = 0.12 W/m.K Plasterboard: kp = 0.17 W/m. K (a) Sketch the thermal circuit for the system. Label heat flow (W) direction,all temperatures, label all resistances. Write expression for all resistances. (b) Determine the total heat loss through the wall.

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