11.4 Sales of People magazine are compared over a 5-week period ...

     11.4 Sales   of People magazine are compared over a 5-week period at four Borders outlets   in Chicago. Does the data prove a significant difference in mean weekly   sales? Magazines GPA for Randomly Selected Students in Four Business Majors   Store 1 Store 2 Store 3 Store 4 102 97 89 100 106 77 91 116 105 82 75 87 115   80 106 102 112 101 94 100 11.6