business stats
posted by jenny .
Given the following information about a hypothesis test of the difference between two means based on independent random samples, which one of the following is the correct rejection region at a significance level of .05? Assume that the samples are obtained from normally distributed populations having equal variances.
H0: μA ≤ μB, H1: μA >μB 1 = 12, 2 = 9, s1 = 4, s2=2, n1 = 13, n2 = 10.
A. Reject H0 if Z > 1.96
B. Reject H0 if Z > 1.645
C. Reject H0 if t > 2.08
D. Reject H0 if t > 1.782

I'll give you a hint.
H1 tells you if the test is onetailed or twotailed. If H1 shows a specific direction, like > or <, then the test is onetailed. If the test does not show a specific direction, then the test is twotailed. Therefore, since H1 shows a specific direction, look at the appropriate table for a onetailed test at .05 level of significance.
I'll let you take it from here.