Refer to the Teaching of Psychology (Aug. 1998) study of whether a practice test helps students prepare for a final exam, presented in Exercise. Recall that students in an introductory psychology class were grouped according to their class standing and whether they attended a review session or took a practice test prior to the final exam. The experimental design was a 3 X 2 factorial designs, with Class Standing at 3 levels (low, medium, high) and Exam Preparation at 2 levels (practice exam, review session). There were 22 students in each of the 3 X 2 = 6 treatment groups. After completing the final exam, each student rated her or his exam preparation on an 11-point scale ranging from 0 (not helpful at all) to 10 (extremely helpful). The data for this experiment (simulated from summary statistics provided in the article) are saved in the PRACEXAM file. The first five and last five observations in the data set are listed in the accompanying table. Conduct a complete analysis of variance of the helpfulness ratings data, including (if war ranted) multiple comparisons of means. Do your findings support the article's conclusion that "Students at all levels of academic ability benefit from ac practice exam"?