A well-insulated heat exchanger is used to heat water (cp = 4.18 KJ/kg*K) from 300 K to 90°C with a mass flow rate of 3 kg/s. Heat is supplied by hot oil (cp = 2.3 KJ/kg*K) that enters the heat exchanger at 200°C with a mass flow rate of 15 kg/s. Determine the exit temperature of the oil, and the entropy generation of the heat exchanger. If instead of making this calculation, you had measured the exit temperature of the oil at 300K, comment on whether or not this is possible? Is your thermometer broken?