kindly solve it for me. This is a problem from replacement analysis.

6. A machine has been installed for $15000 in a plant before 12 years. The company is considering replacing it because of increasing maintenance cost. The estimated maintenance costs for the next year is $1000 and then keeps on increasing at the rate of $200 per year for next 5 years. Whenever the machine is removed the cost of removal will be $1200 more than the machine's worth as scrap metal. The replacement is having an equivalent annual cost of $1000 at its most economic life. When should the machine be replaced or not to be replaced, if MARR is 20%