Answer:
a. Using a mortgage calculator with the given information, Marisa's monthly mortgage payment would be $1,088 to the nearest dollar.
b. The total cost of the house, including the down payment and all payments made over the 30-year mortgage period, would be $453,020. This is calculated by adding the $55,000 down payment to the total amount borrowed ($195,000) and then adding the total interest paid over the 30 years ($203,020) to get $453,020.
c. Marisa will have spent $203,020 in interest over the 30-year mortgage period. This is calculated by subtracting the total amount of the loan ($195,000) from the total amount paid over the 30 years ($398,020), which leaves $203,020 in interest paid.