An insulated tube carries hot water. The tube is \(2 \mathrm{~cm}\) in diameter (inside), \(100 \mathrm{~m}\) long, and the flow rate of fluid is \(0.5 \mathrm{~kg} / \mathrm{min}\). The tube is made of copper and the wall thickness is \(0.2 \mathrm{~cm}\). The insulation is \(3 \mathrm{~cm}\) thick and its thermal conductivity is \(0.035 \mathrm{~W} / \mathrm{m} \mathrm{K}\). The outer layer of the insulation is held at a constant temperature of \(25^{\circ} \mathrm{C}\). The water enters the tube at \(85^{\circ} \mathrm{C}\). What is the water temperature at the outlet?