You are working with the same experiment as in Problem 11.5.

i. At the 0.05 level of significance, state the decision rule for testing the null hypothesis that all four groups have equal population means.

ii. What is your statistical decision?

iii. At the 0.05 level of significance, what is the upper-tail critical value from the Studentized range distribution?

iv. To perform the Tukey-Kramer procedure, what is the critical range?