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公元2000年到来之际，人类忽然发现多少年来对生命的认识将被重新改写。1997年克隆羊的诞生，使人类可以利用生物体上的一个非胚胎细胞复制生命；仅仅两年之后的新发现。将使人类可以利用无生命的物质创造出新的生命来。世界权威的科学刊物《科学》杂志报道了这个惊人的发现，科学家已经找到了形成生命所需要的基因数量。这个消息犹如一发重磅炸弹，轰动了科学界。人们认识到，这意味着科学界能够利用没有生命的化学物质在实验室中制造出生命来。美国马里兰州基因组研究所对一种细菌进行层层拆解，一直拆到生命所必需的基因。科学家们发现，构成一个简单生命至少需要265到350个基因，这300个左右的基因是建构生命体最小的分子指令集。该基因研究所的遗传专家克雷格文特尔博士说，这项研究是用生物体全部基因的集合，即基因组 genome)，对生命重新定义。科学界研究的这种细菌生存于人类的生殖器及肺部，是世界上最小的生物体。它不会给人体带来什么疾病，但所含的基因数目少于任何其他已知生物。人类基因数在80000到140000之间，而这种细菌只有480个。克雷格文特尔等人使该细菌中的基因逐个失去活性，如果细菌死亡，说明这一被杀死的基因是该细菌成活所必需的，通过对大量该细菌的测试，他们发现了这种细菌成活所必需的基因。由于这种细菌是最简单的生命形式，因此它所必需的基因数量也就是生命所必需的基因数量。《科学》杂志还报道说，经过分析发现，这种细菌的必需基因中，有100个基因的功能目前仍不清楚。这些未知但却是必需基因的存在，表明人类尚未了解关于基本生命的每一件事。 对美国马里兰州基因研究组的研究的解说，符合文意的一项？（）
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下列说法中不正确的是一项是（）。
根据教育部《1999年全国教育事业发展统计公报》，全国普通中小学校舍建筑面积为 104070万平方米，比上年增加4747万平方米。其中危房741．4万平方米，危房率比上年下降0．3个百分点。普通初中理科实验设备、分组实验条件和图书藏量达标学校占初中总校数的比例分别是：71．5%、68．3%和73．4%，分别比上年提高3．2、3．7和4．3个百分点。小学理科实验设备、分组实验条件和图书藏量达标学校占小学总校数的比例分别是：44．4%、 38．6%和63%，分别比上年提高2．0、2．3和3．8个百分点。 1998年，全国普通中小学校舍建筑面积中危房约是多少万平方米？（）
红盒子比黑盒子大，蓝盒子比黄盒子大但比白盒子小，黄盒子比黑盒子大，白盒子比红盒子小。按从大到小排出各盒子的顺序应该是（）。
As you all know, the United States is a country on wheels. Nearly eight million new cars are made each year; four households out of five own at least one car, and more than a quarter have two each. Yet you’ll be surprised to learn that some of the car-owners even suffer from malnutrition(营养不良).In 1968, a nation-wide survey of malnutrition was made for the first time. It found that 10 million people are suffering in health through inadequate feeding; the causes of their plight(困境) were varied. Unemployment over a long period should be considered as the main factor. And unemployment, strange to say, nine times out of ten results from automation, both in industrial and agricultural areas. For example, in the rural South when a cotton plantation suddenly cuts its force from 100 people to three, the problem to help the displaced arises. So is the case with industrial automation. In fact, probably 2 million jobs are made unnecessary each year in the whole country as a result of the automation process, thus making unemployment a chief social concern. According to government statistics, the number of people unemployed was over 5 percent for the period from t958 to 1963. In July 1981, it rose to 7.8 percent. As a matter of fact, it has long been known that even during the most prosperous periods there have been people without enough to eat. So I think that’s why President Kennedy said in his inauguration speech in 1961, if the government did not help the poor, it could not save the rich.In 1966, the Social Security Administration calculated that a family of four needed an income of $ 3 355 a year to be above the line of poverty. And in 1977, the average poverty line of the country was slightly more than $ 6 200 annual income for a non-farm family of four. According to the Social Security Act, families of that size below poverty line are eligible to receive benefits from the special welfare program. The average weekly payment of benefits now is equivalent to 36 percent of the worker’s normal wage. And the number of people who receive government benefits is increasing. In 1973, social insurance payments by governments, mainly to old age pensioners and people who had lost their jobs or were off work through illness, amounted to $ 86000 million. Those not fully qualified for insurance payments received $ 29000 million in public aid.But problems still exist. Many people are not reached by the anti-poverty prepare, because local authorities and agencies do not want to play their part or do not gave the resources to do so. Some poor people will not accept help for various reasons. Of course, there are some more important factors which lie in the structure of the society, but I don’t consider it necessary to dig into them here. Yet we will perhaps agree that social welfare programs have solved to some extent the problems of feeding, clothing and housing those below the poverty line. On the whole, it perhaps might be said that American people are living a better life than people in most other countries. According to a 1968 survey, ten million Americans found themselves in a difficult health situation chiefly due to （）.
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