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阅读以下文字，完成以下问题。 我们从何而来仅在十年前，科学家们还一致认为大约320万年前的东非阿法种是最早的人类祖先。而2002年考古学家在西非乍得湖畔发现了一个至今有六七百万年历史的化石；他们认为这是近乎完整的人科动物头盖骨化石，该发现[ ]了人们原先关于原始人类历史的概念。这个化石被称为“托迈”，意为“生命的希望”。它很可能是所有原始人类的祖先。 这块头骨，既带有猿的特征，又带有其后的原始人类的特征。它的颅腔很小，与大猩猩的差不多大，但其下半部分较平，不像大猩猩和黑猩猩具有突出的颌骨，而与后来的原始人类相仿。另外，它的上犬齿小，并且第一颗下前臼齿的磨损跟原始人类的很像，而全然不像大猩猩和黑猩猩较尖的下前臼齿。综合这些特征，化石发现者们坚信他们找到的是一个新的人科动物。 然而，这个结果一经发布便引起了古人类学界的争议。一个进行同类研究的小组认为“托迈”可能是已经灭绝的类人猿或大猩猩的祖先，理由是没有发现能证明其直立行走的骨骼骨——这是作为区分原始人类与古猿的关键特征。而已经目睹过“托迈”风采的人则不予认同。他们表示，从外表特征上判断，“托迈”很可能是原始人类。不管争论的结果如何，不可否认的是，生活在人与猿分化关键时期的“托迈”证明了人类进化的路线的多分支特性。 “托迈”的发现地点，对人类学研究也同样具有革命性意义。在“托迈”之前发现的最古老的人科动物化石分别出土于埃塞俄比亚和肯尼亚。东非大裂谷的东支出土了如此之多又如此之古老的原始人类化石，以至于有些科学家认为，裂谷起了地理隔离作用，裂谷东边干旱、开阔的环境迫使古猿走下树，发展成为人；而在气候湿润、森林茂密的西边，猿仍然生活在树上。这种说法被称为“东边的故事”。 但是，法国古生物学家布鲁内于1995年在乍得挖出一个有350万年历史的颚骨化石，这为“西边的故事”写下了一个开头。“托迈”的出土，又为这个故事描下了重重的一笔。 文中[ ]应填入的词语是( )。
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三、根据下列资料，回答以下问题 据某市海关统计，今年前两个月该市外贸进出口总值为53.67亿美元，比去年同期增长28.7%。其中出口26.38亿美元，增长27.4%，进口27.29亿美元，增长30.1%。2月份当月该市外贸进出口总值为29.69亿美元，比去年同期增长58.2%，增速比1月份加快53.6个百分点。其中：出口14.75亿美元，增长55.4%，增速比1月份加快51.7个百分点；进口14.95亿美元，增长61.1%，增速比1月份加快55.6个百分点。 今年前两个月，一般贸易出口8.97亿美元，增长31%，与一月份增幅基本持平，一般贸易出口增幅高于全市出口平均增幅3.6个百分点。全市加工贸易出口16.67亿美元，比去年同期增长24.8%，扭转了一月份同比下降的局面。 今年前两个月，集体、私营企业出口0.96亿美元，比去年同期增长71.4%，在1月份增长 51.5%的基础上又提高19.9个百分点；外资企业出口21.92亿美元，比去年同期增长33.2%，比 1月份增长2.5%的增幅提高30.7个百分点，占该市出口的比重由上年的79.5%提高到今年的 83%，提高3.5个百分点。 国有企业出口出现下降，今年前两个月国有企业出口3.49亿美元，下降5.2%，而1月份国有企业出口仅增长9.1%，国有企业出口增长出现的这种变化值得关注。 今年前两个月，该市对亚洲出口12.2亿美元，比去年同期增长2.8亿美元；对欧洲出口 5.11亿美元，比去年同期增长1.61亿美元；对拉丁美洲出口0.79亿美元，比去年同期增长0.32亿美元。对北美洲和大洋洲出口分别增长12.2%和37.5%。 今年前两个月，该市对外出口超亿美元的国家有六个国家和地区，分别是美国、日本、韩国、德国、新加坡和香港。六个国家和地区出口总额为18.38亿美元，占全市出口总额的69.7%。其中对美国出口7.3亿美元，增长12.2%，扭转了一月份下降的局面。对日本出口2.99亿美元，增长16.2%；对韩国出口2.66亿美元，增长32%；对德国出口2.46亿美元，增长1.2倍；对新加坡出口1.62亿美元，增长1.8倍；对香港出口1.35亿美元，增长25.4%。 今年前两个月该市出口增长达到27.4%，在全国十大出口省市中该市的出口增幅排在第七位，比全国平均出口增长28.7%的增幅低1.3个百分点。 与去年同期相比，该市对下列哪一地区的出口增长最快( )。
The importance of agriculture cannot be overstated. More than 50 percent of the world’’s labor force is employed in agriculture. The distribution in the early 1980s ranged from 67 percent of those employed in Africa to less than 5 percent in North America. In Western Europe, the figure was about 16 percent; in Eastern Europe and the Soviet Union, about 32 percent; and in Asia, about 68 percent.Farm size varies widely from region to region. Recently the average for Canadian farms was about 186 ha (about 460 acres) per farm, and for U.S. farms, about 175 ha (about 432 acres). The average size of a single landholding in the Philippines, however, may be somewhat less than 3.6 ha (less than 9 acres), and in Indonesia, a little less than 1.2 ha (less than 3 acres).Size also depends on the purpose of the farm. Commercial farming, or production for cash, is usually done on large holdings. The plantations of Latin America are large, privately owned estates worked by tenant labor. Single-crop plantations produce tea, rubber, cocoa. Wheat farms are most efficient when they comprise some thousands of hectares and can be worked by teams of people and machines. Australian sheep stations and other livestock farms must be large to provide grazing for thousands of animals.Individual subsistence farms or small-family mixed-farm operations are decreasing in number in developed countries but are still numerous in the developing countries of Africa and Asia. A "back-to-the-land" movement in the U.S. reversed the decline of small farms in New England and Alaska in the decade from 1970 to 1980.The conditions that determine what will be raised in an area include climate, water supply, and terrain.Over the 10,000 years since agriculture began to be developed, peoples everywhere have discovered the food value of wild plants and animals and domesticated and bred them. The most important are cereals such as wheat, rice, barley, corn and rye.Agricultural income is also derived from non-food crops such as rubber, fiber plants, tobacco, and oilseeds used in synthetic chemical compounds. Money is also derived from raising animals for pelt.Much of the foreign exchange earned by a country may be derived from a single commodity; for example, Sri Lanka depends on tea, Denmark specializes in dairy products, Australia in wool, and New Zealand and Argentina in meat products. In the U.S., wheat has become a major foreign exchange commodity in recent years.The importance of an individual country as an exporter of agricultural products depends on many variables. Among them is the possibility that the country is too little developed industrially to produce manufactured goods in sufficient quantity or technical sophistication. Such agricultural exporters include Ghana with cocoa, and Myanmar with rice. On the other hand, an exceptionally well-developed country may produce surpluses not needed by its own population; this has been true of the U.S., Canada, and some of the West European countries.
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