De Trader opens a brokerage account and purchases 300 shares of Internet Dreams at $40 per share. She borrows $4,000 from her broker to help pay for the purchase.

The interest rate on the loan is 8%.

1. What is the margin in De's account when she first purchases the stock?
2. If the share price falls to $30 per share by the end of the year, what is the remaining margin in her account?
3. If the maintenance margin requirement is 30%,