018 10.0 points A steam engine (assume a Carnot engine ) has an efciency of 78.7%. If the waste heat has a temperature of 763C, what is the temperature of the boiler? Answer in units of 0C. 019 (part 1 of 2) 10.0 points A Carnot engine has a power output of 82 kW. The engine operates between two reservoirs at 30C and 524C. How much thermal energy is absorbed each hour? Answer in units of J. 020 (part 2 of 2) 10.0 points How much thermal energy is lost per hour? Answer in units of J. 014 10.0 points An engine using 1 mol of an ideal gas ini- tially at 20.4 L and 296 K performs a cycle consisting of four steps: 1) an isothermal expansion at 296 K from 20.4 L to 38.1 L ; 2) cooling at constant volume to 140 K ; 3) an isothermal compression to its original volume of 20.4 L; and 4) heating at constant volume to its original temperature of 296 K . Find its efficiency. Assume that the heat capacity is 21 J/K and the univer- sal gas constant is 0.08206 L . atm /mol/K = 8.314 J/mol/K