I HAVE THE ANSWERS BUT I NEED THE WORK TO GET TO THE ANSWER. please use Time Value of Money on a financial calulator

Suppose you take a $145,000 thirty-year fixed-rate mortgage at 6.50%, two discount points, monthly payments. At the end of the first year you inherit $12,000 from your now-favorite uncle. You decide to apply this $12,000 to the principal balance of your loan.

A. How many monthly payments are remaining after the extra lump sum payment is made? ANSWER IS: 277.34

B. What is your net interest savings over the life of the loan by doing this, assuming the loan is held for its full term? ANSWER IS: 52,758