$5\mathrm{.}37$ Assume that $25$ years ago your dad invested $$200,000,$ plus $$25,000$ in years $2$ through $5,$ and $$40,000$ per year from year $6$ on ward. At a very good interest rate of $12\%$ per year, determine $($a$)$ the CC value, and $($b$)$ the annual retirement amount that he can withdraw forever starting next year $($year $26),$ if no additional investments are made.