Mahmut Tutam is considering making an investment of $$80,000$ in a venture that is projected to yield annual returns over a $15-$year period with the following cash flow profile:

$\backslash$table$[[$Year$,$Cash Flow,Year,Cash Flow,Year,Cash Flow$],[1,$$$10,000,6,$$$15,000,11,$$$15,000(0\mathrm{.}7{)}^5$