We buy a car for $50,000. They charge us 8% annual interest. We pay the loan off quarterly. We want to know the effective annual ROR and the quarterly amount to pay off the loan in 5 years. Furthermore, if we had enough after 3 years, how much do we need to give the lender to amortize? If we gave the lender 2,000 in addition to our regular amount after 4 years, how many more payments would we need to give?