9. An investor buys a European put on a share for $4. The stock price is S44 and the strike price is $39. Under what circumstances does the investor make a profit? Under what circumstances will the option be exercised? Draw a diagram showing the variation of the investor's profit with the stock price at the maturity of the option. 10. Explain why margin accounts are required when clients write options but not when they buy options. Why margin accounts are required for both sides of the futures contract trade