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Water at the rate of 1.133 kg/s is heated from 35C to 70C by an oil having a specific heat of 1.9 kJ/kg.K. The heating fluid is available at 130C. The fluids are used in a counter flow double pipe heat exchanger. (a) The water flows inside the tube (k = 377 W/m.K) having an inside diameter of 3 cm, a wall thickness of 0.25cm and a length of 3.53 m. The convective heat transfer coefficients on the inside and outside of the tube are 115 and 1150 W/m.K, respectively. Estimate the overall heat transfer coefficient based on the outer tube diameter. (10 Marks) (b) Calculate the area required for the heating requirement if the heating fluid has a mass flowrate is 2.85 kg/s. (5 Marks) (c) If instead the heat exchanger is a one shell pass and four tube passes shell-and-tube heat exchanger, calculate the total surface area when all other conditions remain the same. (10 Marks)