A国生产手表需6个劳动日，生产自行车需9个劳动日，B国生产手表需12个劳动日，生产自行车需10个劳动日，根据比较成本说（）。

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成人高等教育 / 国际贸易

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A、
A国生产和出口手表、自行车
B、
B国进口手表、自行车
C、
A国生产和出口手表，B国生产和出口自行车
D、
A国生产和出口自行车，B国生产和出口手表

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国际贸易

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题干选择题 Babies who are breast-fed may be more likely to be successful in life, a new study published Tuesday suggests. The study followed more than 3,000 babies into adulthood in Brazil. The researchers found those who were breast-fed scored slightly higher in intelligence tests in their 30s, stayed in school longer and earned more money than those who were given formula（配方奶粉）. “Breast-feeding not only has short-term benefits, but also breast-feeding has long-term benefits, ” says Bernardo Lessa Horta of the Federal University of Pelotas in Brazil, who led the study being published in The Lancet Global Health. Doctors have long known that breast-feeding can be good for a baby's health. This is especially true in poor countries, where water can be contaminated. For instance, a baby given formula in developing countries is 14 times more likely to die in the first six months than one who's breast-fed. In the U.S., some research has suggested that breast-feeding may raise a baby's IQ（智商）by a few points. But a recent study with siblings（兄弟姐妹）found little advantage to breast-feeding. Horta says these previous studies didn't follow children into adulthood to see if breast-feeding had long-term effects. So Horta analyzed data collected from 3,493 volunteers he and his colleagues have been following since birth. They are now in their 30s. First, the researchers gave the subjects IQ tests. Those who were breast-fed for 12 months or more had IQ test scores that were 3.76 points higher than those who were breast-fed for less than one month, the team found. When Horta and his colleagues looked at how much education the subjects had gotten and how much money they were making, they also found a clear difference: Those who were breast-fed the longest stayed in school for about an extra year and had monthly salaries that were about a third higher. 1. From the passage, we learn that Horta 回答ABC未回答正确答案是：A获得2.00分中的0.00分. A. is from Brazil B. conducts his research in the U.S. C. has 30 researchers on his team 2. Which of the following about those who were breast-fed is NOT mentioned?回答ABC未回答正确答案是：B获得2.00分中的0.00分 A. They stayed longer in school B. They were happier C. They were smarter 3. Which of the following is TRUE?回答ABC未回答正确答案是：C获得2.00分中的0.00分 A. Doctors don't understand the benefits of breast-feeding. B. Horta is concerned with water contamination in poor countries. C. Horta's research project lasted about 30 years 4. The word contaminated in Paragraph 3 is closest in meaning to 回答ABC未回答正确答案是：C获得2.00分中的0.00分. A. finished B. interested C. polluted 5. Which of the following is an appropriate title for this passage?回答ABC未回答正确答案是：C获得2.00分中的0.00分 A. Researchers Have Pointed Out the Disadvantages of Breast-feeding B. Researchers Have Found Out the Shortcomings of Formula C. Breast-feeding Improves Chances of Success反馈参考答案：1~5 ABCCC 1.【答案】A 【考点】细节判断题【详解】首先从题干中我们确定关键词Horta，然后从文章第二段中得知Bernardo Lessa Horta of the Federal University of Pelotas in Brazil可以判断出Horta来自Brazil（巴西）。故A为正确答案。 2. 【答案】B 【考点】细节推理题【详解】从题干上看，这是一个反向推理题，问的是NOT mentioned关于母乳喂养（breast-fed）文章中没有提到什么。从文章第一段研究结果显示，The researchers found those who were breast-fed scored slightly higher in intelligence tests in their 30s, stayed in school longer and earned more money than those who were given formula.母乳喂养的孩子智力水平更高（选项C），受教育时间更长（选项A），收入更多。唯一没有提到的就是他们会更幸福（选项B）。故B为正确答案。 3. 【答案】C 【考点】细节推理题【详解】A选项从第三段的第一句Doctors have long known that breast-feeding can be good for a baby's health. 可以得知也是错的。而B选项说Horta关注贫困国家的水污染问题，也是错的。而C选项说该研究项目持续了大约三十年，从文章第一段和第四段中he and his colleagues have been following since birth. They are now in their 30s.得知，他的研究对象从出生，现在大约30岁左右了。可以推理出研究也进行了大约30年了。故C为正确答案。 4. 【答案】C 【考点】指代题【详解】首先定位contaminated在第三段中的位置，然而看其前一句This is especially true in poor countries, 这种情况发生在贫穷的国家。而且从后面看出，用这种水冲奶粉喂养婴儿，在发展中国家（developing countries）婴儿死亡率较高。可以猜出这种水很可能是被污染了。即polluted（污染了的），故C为正确答案。 5. 【答案】C 【考点】主旨题【详解】A选项是说研究人员指出了母乳喂养的缺点。显然不符合文章的中心思想，全文是说母乳喂养的优点。B选项是说研究人员发现了奶粉喂养的缺点。全文说的是母乳对婴儿成长的益处。C选项，母乳喂养提高了成功的机会，即智商高、受教育程度高、收入高。都是成功的标志。故C为正确答案。人文英语4