Missed two payments to a creditor

  Darwin is a young entrepreneur trying to keep his business afloat. He has missed two payments to a creditor. The first was for $3,485 seven months ago and the second was for $5,320 last month. Darwin has had discussions with his creditor, who is willing to accept $4,000 one month from now and a second payment in full six months from now. If the agreed upon interest rate is 7.35% compounded monthly, what is the amount of the second payment?