5.27 A study 5 years ago reported that the median amount of sleep by American adults is 7.5 hours out of 24 with a standard deviation of 1.5 h and that 5% of the population sleep 6 or less hours while another 5% sleep 9 or more hours. A current sample of eight adults reported their average amounts of sleep per 24 hours as 7.2, 8.3, 5.6, 7.4, 7.8, 5.2, 9.1, and 5.8 hours. Use the most appropriate statistical procedures to determine whether American adults sleep less today than they did 5 years ago and justify your choice. You should at least test hypotheses concerning the quantiles of order 0.05, 0.50, and 0.95.