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Feed-water heaters are used to increase the efficiency of steam power plants. A particular heater is used to preheat 10kg/s of boiler feed water from 20C to 188C at a pressure of 1200kPa by mixing it with saturated steam bled from a turbine at 1200kPa and 188C, as shown in Figure P9.3.33. Although insulated, the heater loses heat at the rate of 50J/g of exiting mixture. What fraction of the exit stream is steam