1. Con?dence level and interval width. Refer to Exercise 8.17. Would a 90% con?dence interval be wider or narrower than the one that you found in that exercise? Verify your results by computing the interval.
2. Student loans larger than $30,000. A survey of 1280 student loan borrowers found that 192 had loans totaling more than $30,000 for their undergraduate education.16 Give a 95% con?dence interval for the proportion of all student loan borrowers who have loans of more than $30,000 for their undergraduate education.