The Turners have purchased a house for $$150,000.$ They made an initial down payment of $$30,000$ and secured a mortgage with interest charged at the rate of $9\%$ per year on the unpaid balance. What monthly payments will the Turners be required to make?

a$.$ Future Value with compound interest

b$.$ Present Value with compound interest

c$.$ Future Value of an Annuity

d$.$ Present Value of an Annuity

e$.$ Sinking Fund

f$.$ Amortization