Question a: Which of the following conditions must be met to conduct a test for the difference in two sample means?
a. Data must be at least of interval scale
b. Populations must be normal
c. Variances in the two populations must be equal
d. A and B correct
Question b: Suppose we test the difference between two proportions at the 0.05 level of significance. If the computed z is -1.07, what is our decision?
a. Reject the null hypothesis
b. Do not reject the null hypothesis
c. Take a larger sample
d. Reserve judgment