Researchers Sharon Peterson and Madeleine Sigman-Grant wanted to compare the overall nutrient intake of American children (ages 2 to 19) who exclusively use skim milk instead of 1%, 2%, or whole milk. The researchers combined children who consumed 1% or 2% milk into a "mixed milk" category. The following data represent the daily calcium intake (in mg) for a random sample of eight children in each category and are based on the results presented in their article "Impact of Adopting Lower-Fat Food Choices on Nutrient Intake of American Children," Pediatrics, Vol. 100, No. 3.

(a) Is there sufficient evidence to support the belief that at least one of the means is different from the others at the a = 0.05 level of significance?
(b) 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.
(c) Draw boxplots of the three categories to support the analytic results obtained in parts (a) and (b).