The Transactional Records Access Clearinghouse at Syracuse University reported data showing the odds of an Internal Revenue Service audit. The following table shows the average adjusted gross income reported and the percent of the returns that were audited for 20 selected IRS districts.

a. Develop the estimated regression equation that could be used to predict the percent audited given the average adjusted gross income reported.
b. At the .05 level of significance, determine whether the adjusted gross income and the percent audited are related.
c. Did the estimated regression equation provide a good fit? Explain.
d. Use the estimated regression equation developed in part (a) to calculate a 95% confidence interval for the expected percent audited for districts with an average adjusted gross income of $35,000.

Adjusted Gross Income (S) Percent Audited District Los Angeles Sacramento Atlanta 36,664 38,845 34,886 32,512 34,531 35,995 37,799 33.876 30,513 30,174 30,060 37,153 34,918 33,291 31,504 29,199 33,072 30,859 32,566 34,296 1.1 L1 1.1 1.0 Dallas Providence San Jose Cheyenne Fargo New Orleans Oklahoma City Houston Portland Phoenix Augusta Albuquerque Greensboro Columbia Nashville Buffalo 0.9 0.9 0.9 0.9 0.8 0.8 0.7 0.7 0.7 0.6 0.6 0.5 0.5 0.5