If the assumptions for a pooled t-interval are satisfied, the formula for a (1 )-level upper confidence bound for the difference, 1 2,

If the assumptions for a pooled t-interval are satisfied, the formula for a (1 ˆ’ α)-level upper confidence bound for the difference, μ1 ˆ’ μ2, between two population means is

For a left-tailed hypothesis test at the significance level α, the null hypothesis H0: μ1 = μ2 will be rejected in favor of the alternative hypothesis Ha: μ1 

a. Exercise 10.39
b. Exercise 10.40

(Ri 2/) + (I/n2).