Suppose a bank manager has developed a new system to reduce customer wait time at branches for teller services. The bank manager hopes that the new system will have a population mean wait time that is less than the population mean time ofthe old system. She obtains a sample of 'I 00 customer wait times from the old system, and 50 customer wait times from the new system. She calculates the sample mean wait time under the new system to be 5.65 minutes with a sample standard deviation of 2 minutes, and the sample mean wait time under the old system was 8 minutes with a sample standard deviation of4 minutes. Using degrees of freedom equal to 75: Use Welch's method to calculate a 99% confidence interval for the difference between the population means (let the old wait times be population 1). Enter the point estimate below