A study was conducted to measure the effectiveness of hypnotism in reducing pain. The measurements are centimeters on a pain scale before and after hypnosis. Assume that the paired sample data are simple random samples and that the differences have a distribution that is approximately normal. Construct a 95% confidence interval for the mean of the "before after" differences. Does hypnotism appear to be effective in reducing pain? Before 6.9 3.9 7.0 7.8 10.8 10.7 7.0 6.3 After 6.3 2.1 7.8 8.9 8.7 6.8 3.1 2.6 E) Construct a 95% confidence interval for the mean of the "before after" differences. m