Assume that you want to test the claim that the paired sample data come from a population for which the mean difference is μd = 0. Compute the value of the t test statistic. Round intermediate calculations to four decimal places as needed and final answers to three decimal places as needed.

Subject A B C D E F G H I
Before 168 180 157 132 202 124 190 210 171
After 162 178 145 125 171 126 180 195 163