7. Suppose you have $10,000 in cash to invest. You decide to sell short $5,000 worth of Kortal stock trading at $25/share and invest the proceeds from your short sale, plus your $10,000 into one-year Canadian Treasury Bills earning 5%. At the end of the year, you decide to liquidate your portfolio when Kortal stock is trading at $3 0/share. The return on your portfolio is closest to: a. -57.5% b. -2.5% c. -l.375% d. 2.5% e. 57.5%