Consider a $329,000; 4.2%; 30 year mortgage. (monthly payment and monthly compounding).

a. If a borrower submits an extra $10,000 towards principal along with the 36th payment, and if all other payments are made according to schedule, what's the projected balance at the end of the 5th year?

b. (Ignoring 5a) If you just turned 23 years old on the day this 30-year mortgage was originated, but would like to have the entire mortgage paid off by the time you are 50, what payment should you make each month?

**please include solutions