you buy a cabin with a $20$ year mortgage to host your famous tap dancing parties. The payments 

 

are $$600$ paid every other week $($assume $26$ payments per year$)$ and the interest rate is $4\mathrm{.}1\%.$ Fifteen

years into the mortgage, you get a huge inheritance and decide to pay off the mortgage in cash with

part of your inheritance. How much do you still owe $15$ years into the mortgage?