A problem with a phone line that prevents a customer from receiving or making calls is upsetting to both the customer and the telecommunications company. Table 4 contains samples of 20 problems reported to two different offices of a telecommunications company and the time to clear these problems (in minutes) from the customers' lines: Central Office I Time to Clear Problems: 1.48 1.75 0.78 2.85 0.52 1.60 4.15 3.97 1.48 3.10 1.02 0.53 0.93 1.60 0.80 1.05 6.32 3.93 5.45 0.97 Central Office II Time to Clear Problems: 7.55 3.75 0.10 1.10 0.60 0.52 3.30 2.10 0.58 4.02 3.75 0.65 1.92 0.60 1.53 4.23 0.08 1.48 1.65 0.72 Is there evidence that Central Office II has made an improvement by reducing the mean waiting time from Office I? (Use alpha = 0.05.) What is the alternative hypothesis for the variance test? A Ha: $12