A couple takes out a mortgage for $600,000 at j₂ = 3%. They plan to make payments once every two weeks over 20 years to pay off the mortgage, with the first payment two weeks from now.

a) What is the size of the payment?

b) Right after 10 years of bi-weekly payments, they decide to pay their mortgage monthly (at the end of each month). What monthly payment will be if the interest rate is j₁₂ = 4% for the next 10 years?