下列关于跨商品套利的说法，正确的是（）。
A.当小麦期货价格高出玉米期货价格的程度远大于市场正常年份的水平，应同时买入玉米期货合约、卖出小麦期货合约进行套利
B.当小麦期货价格高出玉米期货价格的程度远小于市场正常年份的水平，应同时卖出玉米期货合约、买入小麦期货合约进行套利
C.当小麦期货价格高出玉米期货价格的程度远小于市场正常年份的水平，应同时卖出小麦期货合约、买入玉米期货合约进行套利
D.当小麦期货价格高出玉米期货价格的程度远大于市场正常年份的水平，应同时买入小麦期货合约、卖出玉米期货合约进行套利
参考答案：A, B
解析：由于小麦价格通常高于玉米价格，两者之间价差一般为正数。当小麦期货价格高出玉米期货价格的程度远小于市场正常年份的水平，即预期价差会扩大，可以在期货市场买入小麦期货合约，同时卖出玉米期货合约进行套利。
| 阅读理解。 | ||||||
| Read the following six advertisements and answer the questions for each of them. Advertisements (广告) | ||||||
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| 1. The Browns are looking for a new house. Mr. Brown wants to live in the north of town near his workplace. Mrs. Brown wants a house with four bedrooms. The Browns' children don't care what the house is like as long as (只要) the garden is big enough. Why didn't the Browns buy the house in the advertisement? | ||||||
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| A. it was on the wrong side of the town. B. There weren't enough bedrooms. C. There was no dinning room. D. The garden was too big. | ||||||
| 2. Man: Why don't we rent (租、借) one of the Sea view Holiday Flats for our holiday, Mary? They sound just as good as the Sea view Hotel, and it would be much cheaper. Mary: There's one big difference between the holiday flats and the hotel. The hotel would be much less work. Why would Mary rather stay at the hotel? | ||||||
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| A. They wouldn't have to cook. B. It's not so expensive. C. She would enjoy the beautiful gardens. D. It's near the sea. | ||||||
| 3. Tom: There's a new football team standing in the village, Mum. I'm old enough to play in it. We stop school at half past three, so I'd have plenty of time. Mum: Well, I suppose you could do your homework later. But look, Tom, you haven't read the advertisement carefully. You can't possibly play for this team. Why can't Tom play for the new football team? | ||||||
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| A. He's not old enough. B. Tom hasn't read the advertisement carefully. C. School stops too late. D. He has to do his homework | ||||||
| 4. Man: I'm looking for a room to rent. It doesn't matter how big it is. I don't care what colour the walls are or how old the furniture (家具) is. I've got to study for my exams, so the house must be quiet and near the school. Girl: There are some advertisements for rooms in the paper. What about this one? Man: Yes… Yes… that's all right. Oh, dear, no, I don't think it would do. What's wrong with the room in the advertisement about rooms? | ||||||
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| A. It's too small. B. The walls are the wrong colour. C. The man likes old furniture better. D. It's too noisy. | ||||||
| 5. Ann has always wanted to work in a restaurant. She thinks they're exciting places. It's hard work but she isn't lazy. You have to work on Saturdays and Sundays but you get other days off. It's not very well-paid, but who cares about money? Why does Ann want to get the job in the restaurant? | ||||||
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| A. It's an easy job. B. The pay is good and the food is free. C. She thinks it would be fun. D. You get long holidays |
H2+CO2。向容器内加入1molCO和1mol H2O（g）时，生成2/3mol CO2如果通入的H2O（g）改为4mol时，在上述条件下，生成CO2的物质的量为