The Jackson family is interested in buying a home which costs $125,000. The family is applying for a $125,000, 30-year special mortgage. The mortgage has a special repayment structure as the following: For the first 10 years, the family will repay $X per month at the end of each month, with the first payment to be made a month from today; For the second 10 years, the family will repay $3X per quarter at the end of each quarter; For the last 10 years, the family will repay $6X per semi-annually at the end of each half year. . The effective annual rate of interest charged by the bank is 6%. (a) Find the amount of monthly repayment during the first 10 years of their mortgage repayment. (6 marks) (b) After making the repayment at the end of the 19th year, the family decided to pay the remaining balance with one-off payment. What is the amount of the remaining balance? (4 marks)