A researcher was interested in whether the 15,196 employees at her company were more or less intelligent compared to the national average, so she administered the Wechsler Adult Intelligence Test (WAIS) to a random sample of 81 employees and they scored an average of 105 with a standard deviation of 16. The national average on the WAIS is a score of 100 and higher scores indicate higher intelligence.

1. Would she need a one-tailed test or a two-tailed test to answer her question?

2. What is the null hypothesis (in words or formula)?

3. What is the alternative hypothesis (in words or formula)?

4. What would be the shape of the sampling distribution of the mean? Explain.