Neuroscientists conducted research in a Canadian prison to see whether solitary confinement affects brain wave activity. They randomly assigned 20 inmates to two groups, assigning half to solitary confinement and the other half to regular confinement. The data follow: Nonconfined Confined
10.7 9.6
10.7 10.4
10.4 9.7
10.9 10.3
10.5 9.2
10.3 9.3
9.6 9.9
11.1 9.5
11.2 9.0
10.4 10.9

Required:
a. Explain why a paired t-test is not appropriate for testing whether the mean alpha wave frequencies are the same in the two groups.
b. Then perform the appropriate test assuming equal variance.