1, analysis: As mentioned above, the investment income of options comes from two parts: royalty income and option performance income. At the break-even point, these two benefits are just in balance.

(1) Royalty income =-15+11=-4, so the option performance income is 4.

(2) Buying a call option, the higher the price, the more profit, that is, more than 280; When selling a call option, the biggest gain is the premium. If it is higher than 290, it will be passively fulfilled and there will be losses. On the whole, between 280 and 290, there will be option performance income. Option performance income is 4, so the breakeven point is 280+4=284.

2. Analysis: The key to this problem is to understand the meaning of β coefficient. There is a formula in the textbook: (10%-4%)/(20%-4%)=37.5%.

3. Analysis: 95.45

4. Analysis: The range of price limit is 4% of the settlement price of the previous trading day, and 2800-2800 * 4% = 2688.