A personality test has a subsection designed to assess the “honesty” of the test-taker. Suppose that you’re interested in the mean score, , on this subsection among the general population. You decide that you’ll use the mean of a random sample of scores on this subsection to estimate . What is the minimum sample size needed in order for you to be 95% confident that your estimate is within 4 of the true mean? Use the value 21 for the population standard deviation of scores on this subsection.