3. In December 2012, Bill Ackmann, a well-known hedge fund manager, announced that he had taken a short position in Herbalife (HLF) stock. For the sake of the example, let's assume that he short sold 20 million shares at a price of S50. a. Given the Federal Reserve's Initial Margin requirement of 50%, how much of his own capital did he have to put up to make this trade? b. During 2013, Herbalife's share price recovered from a low of $29 at the beginning of 2013 to a high of $77 at the end of 2013. At what price did Bill Ackmann receive a margin call during 2013, assuming that the maintenance margin was 30%? c. How much additional equity (cash) did Ackmann need to put up at that point to bring his margin back to the initial margin of 50%? c. Taking into account the additional equity from b. and that Herbalife paid a dividend of $1.20 per share during 2013, what was the return on Ackmann's short position at the end of 2013? Assume that the deposits in the margin account earned 0% interest