A co-flowing heat exchanger receives air at 800K and 15 MPa and water at 15oC and 100 kPa. The two flows exchange energy as they flow alongside each other to the exit, where the air should be cooled to 350K. Investigate the range of water flows necessary per kilogram per second of air flow and the possible water exit temperatures, with the restriction that the minimum temperature difference between the water and air should be 25oC. Include an estimation for the overall entropy generation in the process per kilogram of air flow. Support your analysis with graphical plots whenever possible to make your analysis easy to follow and understand. Assume that the heat exchanger loses heat to the environment which is at 4oC and estimate the range of that heat loss per kg/s of air flow in order not to violate the Second Law of Thermodynamics (i.e. in order not to get a negative entropy generation amount).