Nontextbook Problems: A. A couple is saving up for retirement and wish to invest in an annuity fund. Twenty-five years from now, they plan to start withdraw monthly payments of $1500 for regular expenses over a future 20-year period, at the end of which the account will be empty. Assuming that a bank offers 3% interest, compounded monthly, over the time of their investment PART A1. How much should the couple's monthly deposits be, during the first 25 years? (Determine a linear model for the twenty years after that period, first.) PART A2. If the couple can only afford to to make $500 monthly deposits instead, then how much earlier will the withdrawals end? Nontextbook Problems: A. A couple is saving up for retirement and wish to invest in an annuity fund. Twenty-five years from now, they plan to start withdraw monthly payments of $1500 for regular expenses over a future 20-year period, at the end of which the account will be empty. Assuming that a bank offers 3% interest, compounded monthly, over the time of their investment PART A1. How much should the couple's monthly deposits be, during the first 25 years? (Determine a linear model for the twenty years after that period, first.) PART A2. If the couple can only afford to to make $500 monthly deposits instead, then how much earlier will the withdrawals end