6. (2opts) To test the effect of a physical training courses on one's ability, the number of sit-ups that a person could do in 1 minute, both before and after the course, was recorded. The 17 randomly selected participants scored as shown in the following table. B: 29, 31, 33, 25, 43, 54, 28, 36, 32, 37, 33, 29, 39, 31, 29, 33, 32 A: 31, 33, 30, 27, 46, 53, 32, 39, 37, 30, 35, 35, 43, 29, 30, 35, 50 a. Can you conclude that a significant amount of improvement took place? Use a = 0.025. b. Find a 90% confidence interval for fa. c. Find k such that P(uq > k) = 95%