7.You are buying a car today and will pay back $419.64 per month for 48 months. You make your first payment today. If the rate is 3.6%, how much did you borrow?

8.You charged $2,657 on a credit card. If you pay the minimum payment per month of $46.81, you will pay it off after making 93 payments. How much total interest will you pay?

9.You borrowed $24,282 to buy a car. If you pay $436.49 per month, you will pay it off after making 65 payments. How much total interest will you pay?

10.An investment that will give you monthly payments for 19 years costs $61,013. If your required return is 9.6%, what is the monthly payment?

please answer with formulas. thanks