Suppose a heat engine is connected to two energy reservoirs, one apool of molten aluminum (660°C) and the other a block of solidmercury (-38.9°C). The engine runs by freezing 1.10 g of aluminum and melting 17.0 g of mercury during each cycle. The heat offusion of aluminum is 3.97 10^5 J/kg; the heat of fusion of mercury is 1.18 10^4. What is the effeciency of this engine?