Determine the t critical value for a two-sided confidence interval in each of the following situations:


a. Confidence level = 95%, df = 10


b. Confidence level = 95%, df = 15


c. Confidence level = 99%, df = 15


d. Confidence level = 99%, n = 5


e. Confidence level =98%, df = 24


f. Confidence level = 99%, n = 38