6. Eight golfers were asked to submit their latest scores on their favorite golf courses. These golfers were each given a set of newly designed clubs. After playing with the new clubs for a few months, the golfers were again asked to submit their latest scores on the same golf courses. The results are summarized below. Golfer Own clubs 1 2 3 4 5 6 7 8 77 80 69 73 73 72 75 77 New clubs 72 81 68 73 75 70 73 75 a. Computea and sd. b. Give a point estimate for - = Hd- c. Construct the 99% confidence interval for -d from these data. d. Test, at the 1% level of significance, the hypothesis that on average golf scores are lower with the new clubs.