Agroup of 463 first-year college students were asked, “about how many hours do you study during a typical week? ” the mean response is 15.3 hours. assume that the study time is normally distributed with a sample standard deviation of 8.5 hours. construct a 99% confidence level interval for the mean study time of all first-year students.

Suppose you just purchased a digital music player and have put 8 tracks on it. after listening to them you decide that you like 4 of the songs. with the random feature on your player, each of the 8 songs is played once in random order. find the probability that among the first two songs played (a) you like both of them. would this be unusual? (b) you like neither of them. (c) you like exactly one of them. (d) redo () if a song can be replayed before all 8 songs are played.