(Margin) You purchase 300 shares of Zoom stock on margin at a price of $55. Your broker requires you to deposit $8,000. Your maintenance margin is 30%. Your borrowing rate from your broker is 10%. (50 points) a. What is your initial margin requirement? b. 1 year later, suppose the stock price rise to $108, what is your return? c. In problem b, what would your return have been had you purchase the stock without margin? d. Given that the maintenance margin is 30%, at what price will you receive margin call at the end of year 1