would you help me please?

Construct a confidence interval for Ud, the mean of the differences d for the population of paired data. Assume that the population of paired differences is normally distributed. The table below shows the weights of 9 subjects before and after following a particular diet for two months.' Subject | U Before 168 180 157 132 202 124 190 210 171 After 162 178 145 125 171 126 180 195 163 Construct a 99% confidence interval for the mean difference of the "before" minus "after" weights. O - 0.6