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问题 选择题

海洋中有丰富的食品、矿产、能源、药物和水产资源等(如图所示)，

下列有关说法正确的是(   )

A．第①步中除去粗盐中的、Ca2+、Mg2+、Fe3+等杂质，加入的药品顺序为：Na2CO3溶液→NaOH溶液→BaCl2溶液→过滤后加盐酸

B．第②步中结晶出的MgCl2·6H2O可在空气中受热分解制无水MgCl2

C．在第③④⑤步中溴元素均被氧化

D．从第③步到第⑤步的目的是浓缩

答案

答案：D

A项，第①步中除去粗盐中的、Ca2+、Mg2+、Fe3+等杂质，加入的药品顺序为： NaOH溶液→BaCl2溶液→Na2CO3溶液→过滤后加盐酸，Na2CO3溶液一定要在BaCl2溶液之后加；B项，第②步中结晶出的MgCl2·6H2O应在HCl气氛中受热分解制无水MgCl2，以抑制MgCl2的水解；C项，在第③⑤步中溴元素被氧化，在第④步中溴元素被还原；D项从第③步到第⑤步的目的是浓缩

单项选择题 A1型题

活跃期延长是指（）。

A.总产程超过24小时者

B.宫口开大3cm至宫口开全超过8小时者

C.总产程不超过3小时者

D.宫口开全后初产妇超过2小时，经产妇超过1小时尚未分娩者

E.从临产至宫口开大3cm，超过16小时者
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单项选择题

In every cultivated language there are two great classes of words which, taken together, comprises the whole vocabulary. First, there are those words (1) which we become acquainted in daily conversation, which we (2) , that is to say, from the (3) of our own family and from our familiar associates, and (4) we should know and use (5) we could not read or write. They (6) the common things of life, and are the stock in trade of all who (7) the language. Such words may be called "popular", since they belong to the people (8) and are not the exclusive (9) of a limited class.

On the other hand, our language (10) a multitude of words which are comparatively (11) used in ordinary conversation. Their meanings are known to every educated person, but there is little (12) to use them at home or in the market-place. Our (13) acquaintance with them comes not from our mother’s (14) or from the talk of our school-mates, (15) from books that we read, lectures that we (16) , or the more (17) conversation of highly educated speakers who are discussing some particular (18) in a style appropriately elevated above the habitual (19) of everyday life. Such words are called "learned", and the (20) between them and the "popular" words is of great importance to a right understanding of linguistic process.

14（）

A.tips

B.mouth

C.lips

D.tongue
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