Emily borrows 18000 dollars from her bank at 4.2 percent convertible monthly. She agrees to make monthly interest payments on the loan and will open a sinking fund to repay the principal with a single payment 5 years from now. The sinking fund earns 0.5 percent per month, and she will make monthly deposits that will increase by 1.6 percent per month. Immediately after the 20th interest payment (which occurs at the same time as her 20th sinking fund deposit), Emily decides to refinance her loan. She will empty the sinking fund account and apply those funds to the principal of her debt. Using the amortization method, she wants to pay off the rest of her loan with 35 more equal payments. The bank agrees, provided its yield on the remaining payments is 7.5 percent convertible monthly. What is the size of each of Emily's new payments?