A finned-tube, cross-flow heat exchanger is to use the exhaust of a gas turbine to heat pressurized water. Laboratory measurements are performed on a prototype version of the exchanger, which has a surface area of \(8 \mathrm{~m}^{2}\), to determine the overall heat transfer coefficient as a function of operating conditions. Measurements made under particular conditions, for which \(\dot{m}_{h}=1.5 \mathrm{~kg} / \mathrm{s}, T_{h, i}=325^{\circ} \mathrm{C}, \dot{m}_{c}=0.5 \mathrm{~kg} / \mathrm{s}\), and \(T_{c, i}=\) \(25^{\circ} \mathrm{C}\), reveal a water outlet temperature of \(T_{c, o}=\) \(125^{\circ} \mathrm{C}\). What is the overall heat transfer coefficient of the exchanger?