The farmer in the previous question wants to purchase a tractor that will cost $140,000. She will make a down payment of $20,000, and take out a loan on the rest of the money at 12% compounded monthly. The loan will be repaid monthly in eight years. How much will the interest and principal payments be for the 11th payment?

The previous question:

A farmer wants to fence an area of 3200 square feet in a rectangular field to protect her olive trees from the wild animals. The fence costs $13, 000, and he makes a down payment in the amount of $3, 000. He would like to borrow the remainder from a bank at an interest rate of 9% compounded monthly. She will pay off the loan monthly for a period of two years.

a) What is the amount of the monthly payment A?

b)The farmer has made 9 payments and wants to figure out the balance remaining immediately after 9th payment. What is that balance?