6. [15%] Two groups of people are surveyed. In a sample of 55 drivers who are single people, they drive, on average, 79 miles per week for trips. In a sample of 70 married people, they drive, on average, 67 miles per week for trips. The sample standard deviations are 16 and 8 miles, respectively. At α = 0.01, can it be concluded that single people do more driving for trips than married people? Explain your answer in details.