2. A statistics professor is used to having a variance in his class grades of no more than 100. He feels that his current group of students is different, and so he examines a random sample of midterm grades (listed below.) At a = 0.05, can it be concluded that the variance in grades exceeds 100?
92.3 89.4 96.7 69.5 88.5 79.2
76.9 65.2 49.1 72.8 67.5 52.8
72.9 68.7 75.8