Rose and Leonard bought their house at the end of March 2005, making their first bi-weekly mortgage payment in April, 2005 (making 20 payments the first year). The house cost $280,000 and they put 25% down. The interest rate has always been 6.5%. They renewed for a 5-year term in March 2010. The mortgage has been amortized over 25 years and they make end-of-period mortgage payments. The couple expects to pay off their mortgage in full before they retire. They have joint creditor life insurance on their mortgage, which is $525 p.a.

a) What amount is remaining on their mortgage on December 31st, 2013?