For a $160,000 loan at 7% annual interest, monthly payments, for 30 years, how much total interest will be paid over the life of the loan?

b. For a $250,000 loan at 6% annual interest, with monthly payments for 15 years, if you pay an additional $100 in principle per month, how much total interest will you pay over the life of the loan?

c.If you pay an additional $75 per month up front, how much LESS interest will you pay over the life of the following loan: Loan Amount: $180,000; 30 years (monthly payment); 7% annual interest rate?