Interpreting a Decision In Exercises 43– 48, determine whether the claim represents the null hypothesis or the alternative hypothesis. If a hypothesis test is performed, how should you interpret a decision that
(a) rejects the null hypothesis?
(b) fails to reject the null hypothesis?
43. Swans A scientist claims that the mean incubation period for swan eggs is less than 40 days.
44. Hourly Wages A government agency claims that more than 75% of full-time workers earn over $538 per week. (Adapted from U.S. Bureau of Labor Statistics)
45. Lawn Mowers A researcher claims that the standard deviation of the life of a certain type of lawn mower is at most 2.8 years.
46. Gas Mileage An automotive manufacturer claims that the standard deviation for the gas mileage of its models is 3.9 miles per gallon.
47. Health Care Visits A researcher claims that less than 16% of people had no health care visits in the past year. (Adapted from National Center for Health Statistics)
48. Calories A sports drink maker claims that the mean calorie content of its beverages is 72 calories per serving.