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Suppose that you sell short 500 shares of Intel, which is currently selling for $20 per share. Your broker requires 40% initial margin in short sales, which you covered using the T- bills in your account. Assume that the maintenance margin is 20%.

How high can Intel's price rise before you get a margin call?

How much money would you have to put into your account in order to satisfy the maintenance margin requirement if the price suddenly jumped to $31 a share?