On 2002/3/1, Peter borrowed $4000, agreeing to pay interest at 8.7%/year compounded monthly. He paid $800 on 2006/4/1 and $1000 on 2008/12/1. He will make two more payments on 2012/11/01 and 2013/9/01, with the payment on 2012/11/01 being 40% higher than that on 2013/9/01. What payment will he make on 2013/9/01? Remark: Dates are given in the format YYYY/MM/DD. Answer: On 2002/3/1, Peter borrowed $4000, agreeing to pay interest at 8.7%/year compounded monthly. He paid $800 on 2006/4/1 and $1000 on 2008/12/1. He will make two more payments on 2012/11/01 and 2013/9/01, with the payment on 2012/11/01 being 40% higher than that on 2013/9/01. What payment will he make on 2013/9/01? Remark: Dates are given in the format YYYY/MM/DD