10.19 [EX10-019] Salt-free diets are often prescribed to people with high blood pressure. The following data values were obtained from an experiment designed to estimate the reduction in diastolic blood pressure as a result of consuming a salt-free diet for 2 weeks. Assume diastolic readings to be normally distributed.

Before 93 106 87 92 102 95 88 110 After 92 102 89 92 101 96 88 105

a. What is the point estimate for the mean reduction in the diastolic reading after 2 weeks on this diet?

b. Find the 98% confidence interval for the mean reduction.