题目内容
The coastlines on the two sides of the Atlantic Ocean present a notable parallelism: the easternmost region of Brazil, in Pernambuco, has a convexity that corresponds almost perfectly with the concavity of the African Gulf of Guinea, while the contours of the African coastline between Rio de Oro and Liberia would, by the same approximation, match those of the Caribbean Sea. Similar correspondences are also observed in many other regions of the earth. This observation began to awaken scientific interest about sixty years ago, when Alfred Wegener, a professor at the University of Hamburg, used it as a basis for formulating a revolutionary theory in geological science. According to Wegener, there was originally only one continent or landmass, which he called Pangea. Inasmuch as continental masses are lighter than tile base on which they rest, he reasoned, they must float on the substratum of igneous rock, known as sima, as ice floes float on the sea. Then why, he asked, might continents not be subject to drifting The rotation of the globe and other forces, he thought, had caused the cracking and, finally, the breaking apart of the original Pangea, along an extensive line represented today by the longitudinal submerged mountain range in the center of the Atlantic. While Africa seems to have remained static, the Americas apparently drifted toward the west until they reached their present position after more than 100 million years. Although the phenomenon seems fantastic, accustomed as we are to the concept of the rigidity and immobility of the continents, on the basis of the distance that separates them it is possible to calculate that the continental drift would have been no greater than two inches per year. Sima, as described in this passage, is ______.
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小王和小刘两同学关于法的分类以及法的渊源的辩论如下：小王认为：①按照法的效力、内容和制定法的程序的不同，法律可以分为一般法和特别法。②国际公约现在是中国法的渊源。③我国的行政法规就是由国家行政机关颁布的法律。小刘认为：①我国数量最大的一类法律渊源就是行政法规。②随着全球化的趋势的不断发展，大陆法系和英美法系的区别在减少，现在判例法已经成为大陆法系的正式的法的渊源。③“试行”和“暂行”的法规的效力同其他法律是一样的。④国务院各部委和地方行政机关制定的规章也是行政法规。他们两人观点正确的是( )。
下列选项中，关于100BASE-T4特征的描述不正确的是( )。
Directions: Read the following passage carefully and then translate each underlined part into Chinese. Desertification in the arid United States is flagrant. Groundwater supplies beneath vast stretches of land are dropping precipitously. Whole river systems have dried up; others are chocked with sediment washed from denuded land. 71. Hundreds of thousands of acres of previously irrigated cropland have been abandoned to wind or weeds. Several million acres of natural grassland are eroding at unnaturally high rates as a result of cultivation or overgrazing. All told, about 225 million acres of land are undergoing severe desertification. 72. Federal subsidies encourage the exploitation of arid land resources. Low-interest loans for irrigation and other water delivery systems encourage farmers, industry, and municipalities to mine groundwater. Federal disaster relief and commodity programs encourage arid-land farmers to plow up natural grassland to plant crops such as wheat and, especially cotton. Federal grazing fees that are well below the free market price encourage overgrazing of the commons. The market, too, provides powerful incentives to exploit arid land resources beyond their carrying capacity. 73. When commodity prices are high relative to the farmer’s or rancher’s operating costs, the return on a production-enhancing investment is invaribly greater than the return on a conservation investment. And when commodity prices are relatively low arid land ranchers and farmers often have to use all their available financial resources to stay solvent. 74. If the United States is, as it appears, well on its way toward overdrawing the arid land resources then the policy choice is simply to pay now for the appropriate remedies or pay far more later, when productive benefits from arid - land resources have been both realized and largely terminated.
长期以来，科学同艺术之间的双边关系一直是剃头担子一头热：科学热恋着艺术，艺术却拒科学于千里之外。 许多大科学家一生钟爱艺术，且懂艺术，从中汲取养料，善养浩然之气，或得到人生的极大安慰。相反，文学艺术家则绝少有热爱、理解自然科学和工程技术世界的。 我们的艺术家对自然科学家望而生畏，敬而远之，原因之一是里面有一大堆高深的数学公式。其实，撇开数学，绕过那一大堆深奥的东西，一门学科的基本思想还是可以被我们理解、欣赏的，这恰如我们虽然看不懂莫扎特乐曲的总谱，却照样能同它的主旋律发生共鸣，击节称赞。
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