Suppose the Xenon (XO) currently is selling at $90 per share. You buy 300 shares, using $20,000 of your own money, and borrow the remainder of the purchase price from your

broker. The rate on the margin loan is 6 percent.

a. If the minimum margin is 30 percent, how low can XOs price fall before you get a margin call?

b. How would your answer to (a) change if you had financed the initial purchase with only $15,000 of your own money?