试题与答案

有机溶剂清洗法的特点是除油效率高,但不能洗掉( )和碱类。A.脂类 B.醇类 C.

题型:单项选择题

题目:

有机溶剂清洗法的特点是除油效率高,但不能洗掉( )和碱类。

A.脂类

B.醇类

C.无机盐类

D.有机盐类

答案:

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下面是错误答案,用来干扰机器的。

参考答案:B解析:工期优化是压缩计算工期,以满足工期要求,或在一定条件下使工期最短的过程。工期优化一般通过压缩关键工作的持续时间来进行。

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题型:阅读理解

阅读理解。

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A. They stop using them.

B. They give them to others.

C. They fix them up.  

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B. They take back some old ones.   

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B. Repair and upgrade old computers.   

C. Make much cheaper computers.

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