Understanding Basic Statistics 6th Edition by Charles Henry Brase,Corrinne Pellillo Brase

Exercise 45

Chrysler Concorde: Acceleration Consumer Report stated that the mean time for a Chrysler Concorde to go from 0 to 60 miles per hour is 8.7 seconds.
(a) If you want to set up a statistical test to challenge the claim of 8.7 seconds, what would you use for the null hypothesis
(b) The town of Leadville, colorado, has an elevation over 10,000 feet. Suppose you wanted to test the claim that the average time to accelerate from 0 to 60 miles per hour is longer in Leadville (because of less oxygen). What would you use for the alternate hypothesis
(c) Suppose you made an engine modification and you think that the average time to accelerate from 0 to 60 miles per hour has is reduced. What would you use for the alternate hypothesis
(d) For each of the tests in parts (b) through (c), would the P -value area be on the left, on the right, or on both sides of the mean Explain your answer in each case.