Suppose that you know that a variable is normally distributed on each of two populations. Further suppose that you want to perform a hypothesis test based on independent random samples to compare the two population means. In each case, decide whether you would use the pooled or nonpooled t-test, and give a reason for your answer.
a. You know that the population standard deviations are equal.
b. You know that the population standard deviations are not equal.
c. The sample standard deviations are 23.6 and 25.2, and each sample size is 25.
d. The sample standard deviations are 23.6 and 59.2.