a) State a method how to increase the efficiency of a Carnot heat engine. b) A heat engine is operating on a Carnot cycle and has a thermal efficiency of 75%. The waste heat from this engine is rejected to nearby lake with temperature of 23C at a rate of 700 kJ/min. i) Sketch the schematic diagram of the heat engine. ii) Determine the power out of the engine, kW. iii) Calculate the hot thermal reservoir temperature, C.