Starting in 1998, a series of credit card usage studies have been performed by Sallie Mae, a major provider of educational loans and savings programs. In a recent pilot study, a random pool of 122 loan applicants attending four-year colleges had their credit card data pulled for analysis. The sample mean credit card balance was $3173. The standard deviation was $3216.

(a) Compute a 95% confidence interval for the mean credit card balance among all undergraduate loan applicants (studying at four-year colleges).