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问题 单项选择题

银联信息处理中心于每个工作日（）之前，将上一清算日产生的资金清算信息以即时转账报文的形式提交支付系统，由支付系统实施资金划拨。

A.10：00

B.12：00

C.14：00

D.16：00

答案

参考答案：B

选择题

图甲与图乙是不同放大倍数的某细胞结构模式图，图乙中的①～⑧指细胞内的相关结构。下列关于此图的叙述，正确的是

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A．图甲可能是小麦的根尖细胞

B．⑦只存在于细胞溶胶中

C．具有膜结构的细胞器有①②④⑤⑥⑧

D．染色体主要存在于③中，①中含有DNA分子
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问答题

Passage 1 Development of the City Whatever the particular circumstances of a city, though, its vigour was likely to be affected by technological change. Just as it was improvements in farming that brought about the surpluses that made possible the first fixed settlements, so it was improvements in transport that made possible the development of trade on which the prosperity of so many cities depended. Other technological changes made it possible to survive in a city. The Romans, for instance, constructed aqueducts to bring fresh water to their towns and sewers to provide sanitation. But only the rich benefited. Most Romans, and many city-dwellers throughout history, lived in squalor, and many died of it. Towns were crowded and insanitary; people were often malnourished; and disease spread fast. Though cities grew in size and number for long periods, they could decline and fall, too. Between 1000 and 1300 Europe’s urban population more than doubled, to about 70m (thanks partly to a new system of crop rotation, made possible by better tools). Then, with the Black Death, it fell by a quarter. Country people died too, but the city-dwellers were especially vulnerable. Their health depended above all on clean water and sanitation, which few had, and cheap soap and medicines, which had yet to be invented. Not surprisingly, the next big change in the development of the city also turned on a leap in technology: the invention of engines and manufacturing machinery. The Industrial Revolution did nothing at first to make urban life easier, but it did provide jobs—lots of them. With the new factories of the industrial age that began in the late 18th century was born an entirely new urban era. Peasants left the land in their multitudes to live in new cities, first in the north of England, then all over Europe and North America. By 1900, 13% of the world’s population had become urban.
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