A lump-sum loan of $5,000 is needed by Chandra to pay for college expenses. She has obtained small consumer loans with 12% interest per year in the past to help pay for college. But her father has advised Chandra to apply for a PLUS student loan charging only 8.5% interest per year. If the loan will be repaid in full in five years, what is the difference in total interest accumulated by these two types of student loans?