If you wish to estimate the difference between two population means when the population variances are known, the 99% confidence interval estimate can be developed using which of the following critical values of z?
A) 2.575
B) 1.645
C) 2.325
D) 1.275
E) 2.582

Question

Quizplus · Accepted Answer

The critical value of z for a 99% confidence level with two-tailed test is 2.575.

If You Wish to Estimate the Difference Between Two Population