It is estimated that the average principal owed for student loans in 2014 was $28,950 per student.† if market rates go up and the interest rate for student loans increases from 4.29% to 6.8%, estimate how much more interest students will pay over a 10-year repayment period for this average amount owed, at the 6.8% rate as compared with a rate of 4.29%. round all figures to the nearest cent.