An experiment was designed to compare the lengths of time that four different drugs provided pain relief after surgery. The results (in hours) follow.

Drug Drug A B C D A B C D 8 6 8 4 2 4 10 6 6 10 4 12 4 4 10 2 Is there enough evidence to reject the null hypothesis that there is no significant difference in the length of pain relief provided by the four drugs at   0.05?

a. Solve using the p-value approach.

b. Solve using the classical approach.