A private equity firm XYZ performs a leveraged buyout in which they purchase all equity and debt of company ABC for $$5$ billion. XYZ finances this purchase with $$1$ billion of their own capital and borrows the remaining $$4$ billion at $5\%$ interest. In one year $($unusually short for LBO$),$ XYZ pays off the debt and sells ABC for $$7\mathrm{.}5$ billion. Which of the follow is closest to XYZ$$s return on their invested capital $($the $$1$ billion$)?$ Hint: draw a balance sheet.

$($a$)100\%($b$)200\%($c$)250\%($d$)300\%$

$($e$)$ None of the above