A study compared five dierent methods for teaching descriptive statistics. The five methods were traditional lecture and discussion, programmed textbook instruction, programmed text with lectures, computer instruction, and computer instruction with lectures. 45 students were randomly assigned, 9 to each method. After completing the course, students took a 1-hour exam.

a. What are the hypotheses for evaluating if the average test scores are dierent for the dierent teaching methods?
b. What are the degrees of freedom associated with the F-test for evaluating these hypotheses?
c. Suppose the p-value for this test is 0.0168. What is the conclusion?