A $28 000 mortgage is amortized by quarterly payments over

A $28 000 mortgage is amortized by quarterly payments over 20 years. The mortgage is renewable after 3 years and interest is 6% com- pounded semi-annually.
(a) What is the size of the quarterly payments?
(b) How much interest will be paid during the first year?
(c) What is the balance at the end of the 3-year term?
(d) If the mortgage is renewed for another three years at 7% compounded annually, what will be the size of the quarterly payments for the renewal period?