Question No. 3 Water flows at 50°C inside a 2.5 cm inside diameter tube such that h, 3500 W/m2.°C. The tube has a wall thickness of 0.8 mm with a thermal conductivity of 16 W/m-°C. The outside tube loses heat by free convection with h. 7.6 W/m2.°C. Calculate the overall heat transfer coefficient and heat loss per unit length to surrounding air at 20°C. [2] = of the