Paired records, {(Xi, Yi) : 1 i 16}, were collected for a study of blood pressure change among patients who took prescriptions. The sample summaries for X = blood pressure before and Y = blood pressure after treatment were found as follows:

X =160 and Y =140, with the standard deviation = S based on differences, {Yi Xi : 1 i 16} equal to S = 32.

1. At the significance level, = 0.01, is there enough evidence that the population average blood pressure after is lower than before?

2. At the significance level, = 0.05, is there enough evidence that treatment has any impact, so that the population average after differs from what was before?

Show critical value and state the rejection rule in each case!