A heat exchanger operates at steady state with negligible kinetic and potential energy effects. In one stream, liquid water enters at 10oC and exits at 20oC with negligible change in pressure. In the other stream, R-134a enters at 1 MPa, 80oC and exits at 10 MPa, 20oC. The flowrate of the refrigerant is 125 kg/h. The outer surfaces of the heat exchanger are well-insulated. Determine (a) the mass flowrate of the liquid water, in kg/h, (b) the entropy change of water within the exchanger, (c) the entropy change of R-134a within the exchanger and (d) the rate of entropy production within the heat exchanger in kW/K.