A double pipe heat exchanger is made of a 6-nom sch 40 commercial steel outer pipe and a 5-nom sch 40S stainless steel inner pipe. The fluid in the annular space is cyclohexane that has a volumetric flow rate of 50,000 lbm/h and an average temperature of 180°F. The fluid in the inner tube is river water at an average temperature of 60°F and flowing at 125,000 lbm/h. The thermal conductivity of the inner pipe is 9.5 Btu/h-ft-°F. Determine the overall heat transfer coefficient, based on the outside diameter of the inner pipe for a clean heat exchanger.