in the northern hemisphere, dolphins swim predominantly in a counterclockwise direction while sleeping. a group of researchers wanted to know whether the same was true for dolphins in the southern hemisphere. they watched 8 sleeping dolphins, and found that they swam in a clockwise direction while sleeping the following percentages of time. data: 77.7, 84.8, 79.4, 84.0, 99.6, 93.6, 89.4, 97.2 assume that this is a random sample and that this variable has a normal distribution in the population. what is the 99% confidence interval for the mean time swimming clockwise in the southern hemisphere?