A balloon mortgage requires you to pay off part of a loan during a specified period and then make a lump sum payment to pay off the remaining portion of the loan. Suppose you borrow $400,000 on a 20-year balloon mortgage, and the interest rate is .5 percent per month. Your end-of-month payments during the first 20 years are required to pay off $300,000 of your loan, at which point, you have to pay off the remaining $100,000. Determine your monthly payments for this loan.

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