1. Short Sales An investor short-sells 100 shares of stock, which currently sells for $21 per share. As a margin, the investor deposits $1,000-worth Treasury bill to the account. The broker requires that the maintenance margin is 30%. a) How high can the share price increase before the investor receives a margin call? b) Suppose that the investor closes the short-selling position a year later (buy shares and return to the original owner). The stock price then becomes $15. What is the profit from the short sales