Abby has a subsidized student loan for $78,000.00 and plans to pay it off in 7 years with an annual interest rate is 4.642%, compounded each month.

a) Calculate Abby's monthly payment. Round to the nearest cent.

b) How much will Abby have to pay in total to pay off this loan? Round to the nearest cent.

c) How much interest will Abby pay in total over the life of the loan as it's currently structured? Round to the nearest cent.