The mean duration of a Major League baseball game from the first pitch to the last out over the first eight weeks of the 2013 season was 2 hours and 58 minutes.5 During the second half of the season,...

The mean duration of a Major League baseball game from the first pitch to the last out over the first eight weeks of the 2013 season was 2 hours and 58 minutes.5 During the second half of the season, Major League umpires tried various techniques to speed up the game. A random sample of second-half games will be selected, and the resulting game durations will be used to determine whether games take less time to complete. Let u be the mean duration of a baseball game. State the relevant null and alternative hypotheses in terms of u.

DATTCO, a school bus company in New Britain, Connecticut, will install seat belts on all buses if more than 50% of all parents favor this change. A random sample of parents in the school district will be obtained, and the responses will be used to test the relevant hypothesis. If p is the true proportion of parents who favor seat-belt installation, which of the following sets of null and alternative hypotheses is appropriate? Justify your answer.