calculate: "A borrower made a mortgage loan $5$ years ago for $ $100,000$ at $9$percent interest for $30$ years $($monthly payment$).$ After $5$ years, interest rates fall, and new mortage loan is available at $7$ percent for $25$ years. Suppose that the prepayment penalty of $2$ percent must be paid on the existing loan, and the lender requires an origination fee of $$2,500$ plus $ $250$ for incidental closing costs if the new loan is made.$$

Should the borrower refinance?"