a) What is the balance of your current mortgage?

b) Considering the answer given in "a)", if you sell your residence and buy the one closer to your office, what is the amount that has to be financed with a new mortgage?

c) Your financial institution offers you to renegotiate your mortgage. In order to help you with this transaction, it offers you the lowest rate on the market, but you need to pay a penalty of renegotiation of $3500. This penalty is only added to your mortgage balance. The rate is 4.05% for a term of 20 years. For similar terms, the market rate of other institutions is 4.15% and there is no transfer fee. Is your financial institution's proposal really advantageous? Which one will you take?

d) Now that you have chosen the advantageous offer, you want to know what portion of the principle and interest will be repaid during the 25th payment on your new mortgage.