In a study of students at Lewis & Clark Community College, a professor compared the chosen seat location of students in mathematics courses to their overall grade point average (GPA). He randomly selected 10 students from each of three seat locations: (1) front, (2) middle, and (3) back. The GPAs follow:

(a) Explain why this data may be analyzed using a one-way ANOVA.
(b) Test the null hypothesis that the mean score for each location is the same at the a = 0.05 level of significance.
(c) If the null hypothesis is rejected in part (a), use Tukey's test to determine which pairwise means differ using a familywise error rate of a = 0.05.
(d) Draw boxplots of the three treatment levels to support the analytic results obtained in parts (b) and (c).