Mark Green is considering buying a new Honda Accord. The purchase price of the car is $21,000 but Mark has a trade-in worth $4500. Mark needs a loan to buy the car and knows that his local bank requires him to put down 10% of the purchase price after the value of the trade-in is considered. Mark also knows that bank will charge 8% for the loan and require monthly payments over the next 4 years. What is the minimum down payment that Mark can make