10.71 [EX10-071] Twenty laboratory mice were randomly divided into two groups of 10. Each group was fed according to a prescribed diet. At the end of 3 weeks, the weight gained by each animal was recorded. Do the data in the following table justify the conclusion that the mean weight gained on diet B was greater than the mean weight gained on diet A, at the   0.05 level of significance? Assume normality.

Diet A 5 14 7 9 11 7 13 14 12 8 Diet B 5 21 16 23 4 16 13 19 9 21

a. Solve using the p-value approach.

b. Solve using the classical approach.