The following weights in ounces resulted from a sample of laboratory rats on a particular diet. Use α = 0.05 and test whether the diet was effective in reducing weight.

Rat 1 2 3 4 5 6 7 8 9 10 Before 14 27 19 17 19 12 15 15 21 19 After 16 18 17 16 16 11 15 12 21 18 LO.1