5. Trout experiment, continued Exercise 15 of Chap. 3 (p. 67) concerns a study of the effects of four levels of sulfamerazine (0, 5, 10, 15 g per 100 lb of fish) on the hemoglobin content of trout blood. An analysis of variance test rejected the hypothesis that the four treatment effects are the same at significance level α = 0.01.

(a) Compare the four treatments using Tukey’s method of pairwise comparisons and a 99% overall confidence level.

(b) Compare the effect of no sulfamerazine on the hemoglobin content of trout blood with the average effect of the other three levels. The overall confidence level of all intervals in parts

(a) and

(b) should be at least 98%.