Production engineers at Sinotron believe that a modified layout on its assembly lines might increase average worker productivity (measured in the number of units produced per hour). However, before the engineers are ready to install the revised layout officially across the entire firm’s production lines, they would like to study the modified line’s effects on output. The following data represent the average hourly production output of 12 randomly sampled employees before and after the line was modified:

At the 0.05 level of significance, can the production engineers conclude that the modified (after) layout has increased average worker productivity?