Refer to Exercise 36. For the sample data reported there, compute the proportion of students in each class who answered’ yes’ to the survey question. Following the approach described in Section 14.1 for testing proportion differences, use these four sample proportions to test the hypothesis that there would be no difference in the proportion of “yes” responses for students in the four populations (that is, classes) represented. Use a 5% significance level. Comment on the similarities between results in this test and the results of the test of independence you applied to the data in Exercise 36.