Calculate for the following cases, the surface area required for a heat exchanger which is required to cool 3200 kg/h of benzene (Cp=1.74 kJ/kg °C) from 71 °C to 42 °C. The cooling water (Cp =4.18 kJ/kg C) at 15 °C has a flow rate of 2200 kg/h. • (i) Single pass counter-flow, • (ii) 1-4 exchanger (one-shell pass and four-tube passes), and • (ili) Cross flow single pass with water mixed and benzene unmixed. For each configuration, the overall heat transfer coefficient may be taken as 0.28 kW/m2 OC.