Galvin is graduating from college in eighteen months, but he will need a loan in the amount of $9,875 for his last three semesters. he may either receive an unsubsidized stafford loan with an interest rate of 6.8%, compounded monthly, or his parents may get a plus loan with an interest rate of 7.8%, compounded monthly. the stafford loan has a grace period of six months from the time of graduation. which loan will have a higher balance at the time of repayment and by how much?