Consumer Reports indicated that the mean acceleration time (0 to 60 miles per hour) for the Dodge Intrepid was 10.2 seconds. In most tests of this type, regular unleaded gasoline is used. Suppose that 41 such tests were made using premium unleaded gasoline and the sample mean was found to be 9.7 seconds with a sample standard deviation of 2.1 seconds. Does this indicate that premium gasoline tends to reduce average acceleration time