If a fossil fuel power plant operating between 540 and 50C provides the electrical power (W in the diagram below) to run a heat pump that works between 25 and 5C. Calculate the amount of heat pumped into the house per unit amount of heat extracted from the power plant, QHpQH, when efficiency of the power plant is 70% of maximum and that the coefficient of performance of the heat pump is 10% of maximum. Suppose a furnace is used to heat the house instead of the heat pump and uses 80% of the fossil fuel energy. Would it be more economical in terms of overall fossil fuel consumption to use a heat pump or a furnace (when heat pump operates under the condition of (a)