The Data Represent the Measure of a Variable Before and After

The data represent the measure of a variable before and after a treatment. Does the sample evidence suggestthat the treatment is effective in increasing the value of the response variable? Use the α = 0.01 level ofsignificance. Assume that the differenced data come from a population that is normally distributed with nooutliers. $$\begin{array} { c | c c c c c c c } \text { Subject } & \text { A } & \text { B } & \text { C } & \text { D } & \text { E } & \text { F } & \text { G } \\\hline \text { Before, } X _ { \mathrm { i } } & 9.4 & 9.7 & 9.6 & 9.5 & 9.4 & 9.4 & 9.5 \\\hline \text { After, } \mathrm { Y } _ { \mathrm { i } } & 9.5 & 9.9 & 9.6 & 9.4 & 9.5 & 9.7 & 9.3\end{array}$$