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问题 选择题

到目前所知生物圈的领域，包括海平面上下各约几千米？（　　）

A．10

B．20

C．30

D．40

答案

生物圈是地球上的所有生物与其生存的环境形成的一个统一整体，生物圈的范围：以海平面为标准来划分，生物圈向上可到达约10千米的高度，向下可深入10千米左右深处，厚度为20千米左右的圈层，包括大气圈的底部、水圈的大部和岩石圈的表面；包括森林生态系统、海洋生态系统、农田生态系统、草原生态系统、淡水生态系统、湿地生态系统、城市生态系统等等，是最大的生态系统．

故选：A

单项选择题

某医科大学医学专业研究生1999年7月毕业后分配到三级医院从事临床工作，同年12月擅自另行开设诊所独立行医。依据《中华人民共和国执业医师法》其行为属于

A．未取得医师资格非法行医
B．执业医师行医
C．执业助理医师行医
D．个体行医
E．未办理手续非法行医
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单项选择题

Before the printing press, books could be purchased only in expensive manuscript copies. The printing press produced books that were significantly leas expensive than the manuscript editions. The public’s demand for printed books in the first years after the invention of the printing press was many times greater than demand had been for manuscript copies. This increase demonstrates that there was a dramatic jump in the number of people who learned how to read in the years after publishers first started producing books on the printing press.
Which one of the following statements, if true, casts doubt on the argument

A．During the first years after the invention of the printing press, letter writing by people who wrote without the assistance of scribes or clerks exhibited a dramatic increase.

B．Books produced on the printing press are often found with written comments in the margins in the handwriting of the people who owned the books.

C．In the first years after the printing press was invented, printed books were purchased primarily by people who had always bought and read expensive manuscripts but could afford a greater number of printed books for the same money.

D．Books that were printed on the printing press in the first years after its invention often circulated among friends in informal reading clubs or libraries.

E．(E) The first printed books published after the invention of the printing press would have been useless to illiterate people, since the books had virtually no illustrations.
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