You have an outstanding student loan with required payments of $$550$ per month for the next four years. The interest rate on the loan is $9\mathrm{.}75\%$ APR $($monthly$).$ You are considering making an extra payment of $$150$ today $($i$.$e$.,$ you will pay an extra $$150$ that you are not required to pay$).$ If you are required to continue to make payments of $$550$ per month until the loan is paid off, what is the amount of your final payment? What effective rate of return $($expressed as an APR with monthly compounding$)$ have you earned on the $$150?($Note: Be careful not to round any intermediate steps less than six decimal places.$)$

If you are required to continue to make payments of $$550$ per month until the loan is paid off, what is the amount of your final payment?

The final payment is $$.($Round to the nearest cent.$)$