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【单选题】
物质具有芳香性不一定需要的条件是 ( )
A.
环闭的共轭体
B.
体系的 π电子数为 4n+2
C.
有苯环存在
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【单选题】下列化合物酸性次序由强至弱排列正确的是:( ) 1 Cl 2 CHCOOH 2 CH 3 COOH 3 ClCH 2 COOH 4 ClCH 2 CH 2 COOH
A.
② > ① > ③ > ④
B.
② > ④ > ③ > ①
C.
① > ④ > ③ > ②
D.
① > ③ > ④ > ②
【简答题】排列下列化合物酸性强弱的次序( )。 A .苯酚 B .苯甲酸 C .环已醇 D .水
【多选题】下列属于济南市的景区有( )。
A.
趵突泉
B.
难老泉
C.
大明湖
D.
千佛山
【简答题】某型号零件的内径设计尺寸为20mm,公差为(+0.15,0.15)mm,某道工序承担该零件内径的最后加工,现需要通过随机抽样对该工序的工序能力进行评估,共抽取200个样本,经测算,该样本平均值和公差中心重合,标准差为0.08mm。 根据以上资料,回答下列问题: 该工序的工序能力指数为( )。A.2.052 B.1.635 C.1.414 D.0.625 若该工序的工序能力指数为1.5,可以判断该工...
【多选题】在正交平面P0中测量的角度有()
A.
前角
B.
后角
C.
主偏角
D.
副偏角
【判断题】玻璃电极在初次使用前,应先将电极的球膜部分在蒸馏水中或在0.1mol/L的盐酸中浸泡24h以上。
A.
正确
B.
错误
【简答题】从强到弱排列下列化合物的酸性次序: A 苯酚 B 对甲基苯酚 C 对氯苯酚 D 对硝基苯酚 E 对甲氧基苯酚 F 2 , 4- 二硝基苯酚
【单选题】77 Since risk is associated with most projects, the best course of action is to:
A.
cover all project risks by buying appropriate insurance
B.
ignore the risks, since nothing can be done about them and move forward with the project in an expeditious manner.
C.
avoid projects with clear and present risks
D.
eliminate all known risks prior to the execution phase of the project
E.
identify various risks and implement actions to mitigate their potential impact
【简答题】The F.P.A.doesn't cover partial loss of the nature of particular average.
【单选题】Since risk is associated with most projects,the best course of action is to (71)
A.
cover all project risks by buying appropriate insurance
B.
ignore the risks,since nothing can be done about them and move forward with the project in an expeditious manner
C.
avoid project with clear and present risk
D.
identify various risks and implement actions to mitigate their potential impact
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