Remember that for monthly compounding, you get the monthly rate by dividing the APR by 12. Suppose you borrow $9000 at 9% APR (meaning that you use r = 0.09/12 in the preceding formula) and pay it back in 2 years.

(With this information, I deducted: is that correct?)
ANSWER: Yes, correct; t = 24 (2 years = 24 months)

(a) What is your monthly payment? (Round your answer to the nearest cent.)

(Is this t(1)?)
ANSWER: That question makes no sense...

Do the calculation above (with t=24) and you'll get the monthly payment.