One-Tailed and Two-Tailed Tests LEARNING OBJECTIVE: Determine a left-tailed, right-tailed, or two-tailed test from a given null and alternative hypothesis. David hypothesize that the average age of the population of Wyoming is less than 45 years. David records a sample mean equal to 42 and states the hypothesis as = 45 vs < 45. Select the best description for this type of test. a.) Two-tailed test
b.) Left-tailed test
c.) Upper-tailed test
d.) Right-tailed test