State the null and the alternative hypotheses of the following statements. 1. A car dealership announces that the mean time for an oil change is less than 15 minutes. 2. A company advertises that the...

State the null and the alternative hypotheses of the following statements.

1. A car dealership announces that the mean time for an oil change is less than 15 minutes.
2. A company advertises that the mean life of its furnaces is more than 18 years.
3. A consumer analyst reports that the mean life of a certain type of automobile battery is not 74 months.
4. A transportation network company claims that the mean travel time between two destinations is about 16 minutes.