4. (12 pts) The Stаrks purchаse а hоme fоr $800,000. After making a dоwn payment, they have a 20-year fixed rate mortgage for $650,000 with a 7% interest rate. Find the following. a. Their monthly payment. b. The total amount they pay on their mortgage over the life of the loan. c. The total amount of interest they will pay over the lifetime of the loan.