A recent internal report issued by the marketing manager for a national oil-change franchise indicated that the mean number of miles between oil changes for franchise customers is at least 3,600 miles. One Texas franchise owner conducted a study to determine whether the marketing manager's statement was accurate for his franchise's customers. He selected a simple random sample of 10 customers and determined the number of miles each had driven the car between oil changes. The following sample data were obtained:

a. State the appropriate null and alternative hypotheses.
b. Use the test statistic approach with α = 0.05 to test the null hypothesis.

3.655 4.20 946 2.789 3.555 3.734 3.208 3.3 3,920 3.902