用氯化钠配制l00g溶质质量分数为20%的氯化钠溶液,现有下列操作:①溶解;②称

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问题:

用氯化钠配制l00g溶质质量分数为20%的氯化钠溶液,现有下列操作:①溶解;②称取氯化钠;③结晶;④量取水;⑤计算;⑥蒸发.正确的操作顺序是[ ]

A、⑤②④①

B、①②③④

C、①③⑤②④

D、①③⑥⑤②④

考点:溶液的配制
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痰热内郁,风寒外束引起发作者,可以表现为

A.痰少质粘或如絮条
B.痰多黏腻色白
C.痰稀薄而白
D.痰黏稠而黄
E.痰少而黏或带血丝

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按国家规定,企业缴纳基本养老保险费的比例一般不得超过企业工资总额的百分之几?()

A.15%

B.20%

C.25%

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下列软件不属于下载工具软件的是()。

A.迅雷

B.超级旋风

C.Flashget

D.Winrar

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外来化合物

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The relational database model requires the data be (71) through programs that don’t rely on the position of the data in the database. This is in direct (72) to the other database mode, where the program has to follow a series of pointers to the data it seeks. A program (73) a relational database simply asks for the data it seeks; the DBMS performs the necessary searches and (74) the information. The (75) on how the search is done are specific to the DBMS and vary from product to product.

(74)处填()。

A.erases

B.provides

C.proves

D.values

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