A loan of $10,000 is to be repaid with annual payments, at the end of each year, for the next 21 years. For the first 7 years the payments are X per year, the second 7 years they are 2X per year, and for the third 7 years they are 3X per year. 1) Find X if i⁽²⁾ = 10%. 2) Find X if i⁽²⁾ = 8% for the first 10 years and i⁽²⁾ = 12% afterwards.