$($Related to Checkpoint $6\mathrm{.}1)($Future value of an annuity$)$ Imagine that Homer Simpson actually invested the $$100,000$ he earned providing Mr$.$ Burns entertainment $6$ years ago at $10$ percent annual interest and that he starts investing an additional $$2,100$ a year today and at the beginning of each year for $20$ years at the same $10$ percent annual rate. How much money will Homer have $20$ years from today?