A mother made a loan worth $650,000 at an interest rate of 8% per annum payable for fifteen equal annual payments starting at the end of the first year. Six years after she made her first loan, the mother made another loan equal to $100,000 to further expand her storage facility. The second loan, which is also payable in equal annual payments starting the end of the year after she made the loan, should be settled at the same time as the first loan.

a) How much did she pay per annum in the first 6 years?

b) How much will she pay per annum from the end of years 7 to 15?

c) After paying annually for 11 years, the mother chose to settle her loan. How much will she have to pay at the end of the 12th year?