Hot engine oil with heat capacity rate of 4440 W/K (product of mass flow rate and specific heat) and an inlet temperature of 150°C flows through a double pipe heat exchanger. The double pipe heat exchanger is constructed of a 1.5-m-long copper pipe (k = 250 W/m·K) with an inner tube of inside diameter 2 cm and outside tube diameter of 2.25 cm. The inner diameter of the outer tube of the double pipe heat exchanger is 6 cm. Oil flowing at a rate of 2 kg/s through inner tube exits the heat exchanger at a temperature of 50°C. The cold fluid, that is, water enters the heat exchanger at 20°C and exits at 70°C. Assuming the fouling factor on the oil side and water side to be 0.00015 m²·K/W and 0.0001 m²·K/W, respectively, determine the overall heat transfer coefficient on inner and outer surface of the copper tube.