B B C Because you sell both call options and put options at the same time, the exercise price is 15000 points, so when the actual Hang Seng Index is 15000 points in July, your maximum profit is 500+300=800 points. Second question: Similarly, because you sell both bullish and bearish, you can judge that there should be two critical points. Rising to a certain level and falling to a certain level can hedge profits, so you can; 15000-500-300 =14200 This is the lower critical point,15000+500+300 =15800 This is the upper critical point. The third question; It can be inferred from the second question that when the Hang Seng Index is at 15900, you must be losing money, because the price has exceeded your upper critical point, so there is no doubt that you chose C. If you are not sure, you can also bring the value into the calculation. It must be a loss 100 points. Ha ha.

Sorry, I read it wrong. The first supplementary question is that you should make a profit of $0.5 per ounce, because it can offset your profit and loss. Suppose the futures price due in June is $430/oz, you lose $65,438+0/oz in the option, and you gain $ 430-428.5 = $65,438+0.5/oz in the futures market. Of course, I can't work out the answer to the second question, and I can't help you. Reading should not be difficult.