PLEASE READ: The only thing I want to learn are the step by step of what to punch in the calculator HP10BII+ financial calculator, I'm trying to learn what to punch in the financial calculator. I know the answers already. If you can include the formula, I'll extremely appreciate it! Thank you!

Your firm has a loan on a piece of equipment. The loan was secured on January 1 and it is now December 31. You need to compute the interest paid this year on this loan for tax purposes. The loan was $80,000; it was a 10 year loan at 7% with monthly payments. If you have made the first eleven payments, how much interest have you paid this year?