sean needs to borrow $1000 to fly to europe in the summer. his friend tim offers him a loan over two years, at an annual interest rate of 4%. he can also borrow the same amount from his bank at an annual rate of 5%, but the loan needs to be paid back in 18 months. in addition, his cousin offers to loan him the $1000, provided that sean pay her back $1100 in two years. which of the following statements is true?