4. Heat exchange (energy and mass conservation)A heat exchanger is used to heat cold water at 15°C entering at a rate of 2 kg/s by hot air at 85°C enteringat a rate of 3 kg/s. The heat exchanger is not insulated and is losing heat at a rate of 30 kJ/s. The specificheat capacities of air and water can be found in the lesson slides. If the exit temperature of hot air is 20°C,choose the correct exit temperature for the cold water:а. 28°Cb. 35°Cс. 38°Cd. 41°Ce. 80°C

The mass flow rate of cold water m˙cw=2 kg/s Inlet temperatures of cold water T1=150CHeat lost from…

Answered: A heat exchanger is used to heat cold…

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