Please answer these four and explain how to get answer for #12 please. :)

12. You sold short 300 shares of common stock at $55 per share. The initial margin is 60%. At what stock price would you receive a margin call if the maintenance margin is 35%? A. $51.00 B. $65.18 C. $35.22 D. $40.36 E none of the above 13. The interest rate that commercial banks charge their most credit-worthy customers is known as the A. call rate B. fed funds rate C. discount rate D. LIBOR rate E prime rate The interest rate charged by banks on loans made to broker-dealers, who use these loan proceeds to make margin loans to their clients is known as the A. call rate B. fed funds rate C. discount rate D. LIBOR rate E prime rate 14. 15 Buying on margin increases the financial risk of the investment beyond the risk inherent in the security itself. A) Truc B) False