The following 5 questions are based on this information.

Based on a random sample of30 U.S. workers, a researcher found that the average (X) number of vacation days a U.S. worker takes per year is 16. The sample standard deviation (s) is 12 days.

The goal is to construct a 99% confidence interval for theaverage () number of vacation days taken by U.S. workers per year. Assume that the number vacation days taken by U.S. workers is normally distributed.

1)The standard error (SE) ofX is

2)The critical value (CV) needed for 99% confidence interval estimation is

3)The 99% confidence interval estimate of is 4)Suppose CEO of a company claims that the yearly average vacation days of all U.S. workers is 18 days. In light of the sample evidence and at the 1% level of significance, reject?

5)If we decrease the confidence level (1-) from 0.99 to 0.95, the margin of error (ME) of the confidence interval estimate will