For the situation in Problem 20.35, suppose that the flowrate of the process stream must be reduced while keeping the process exit temperature at 51°C. Therefore, it will be necessary to reduce the flow of the cooling water stream. Determine the maximum scale-down of the process fluid that can occur without the exit cooling water temperature exceeding the limit of 45°C (when excessive fouling is known to occur). Plot the results as the ratio of the process stream flowrate to the base-case value (xaxis) versus the cooling water exit temperature.