04: Several retired bicycle racers are coaching a large group of young prospects. They randomly select seven of their riders to take part in a test of the effectiveness of a new dietary supplement that is supposed to increase strength and stamina. Each of the seven riders does a time trial on the same course. Then they all take the dietary supplement for 4 weeks. All other aspects of their training program remain as they were prior to the time trial. At the end of the 4 weeks, these riders do another time trial on the same course. The times (in minutes) recorded by each rider for these trials before and after the 4-week period are shown in the following table: Before After 103 100 97 95 111 104 95 101 102 96 96 91 108 101 Conduct the hypothesis test at the 2.5% significance level whether taking this dietary supplement results in faster times in the time trials. Assume that the population of paired differences is approximately normally distributed