In 2015, the minimum starting salary for a teacher with four years of training in schools in New South Wales, Australia, was AU\$62,282; for a teacher with five years of training, it was AU\$65,486 (The University of Sydney, n.d.). (For simplicity, assume that these salaries stay constant and do not increase with experience.) To maximize your life-time earnings, is it worthwhile to take one extra year of schooling at a cost of AU \(\$ 15,000\) ? In your calculations, assume that in each case, you'll work for 30 years and then retire, and consider interest rates of \(3 \%\) and \(4 \%\).