Ursula took out an unsubsidized Stafford loan to help pay for her first of her four years at college. The loan had a principal of $6,400, an interest rate of 6.9% compounded monthly. After college, Ursula started making monthly payments over a 10 year period on her loan. What percentage of the total cost of the loan is the finance charge?
a.
45.25%
b.
27.91%
c.
43.50%
d.
82.66%