Customer waiting times are studied at the Humber Valley Credit Union. When 25 randomly selected customers enter any one of several waiting lines, their times have a mean of 6.896 min and a standard deviation of 3.619 min. When 20 randomly selected customers enter a single main waiting line that feeds the individual teller stations, their waiting times have a mean of 7.460 min and a standard deviation of 1.841 min. Use a 0.01 significance level to test the claim that waiting times for the single line have a lower standard deviation