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【单选题】
Great changes ______in his hometown in the last twenty years.A.
were taken place
B.
have taken place
C.
have been taken place
D.
took place
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【单选题】分光光度计测定工业水中铬时,下列说法错误的有
A.
酸性溶液中， Cr 6+ 与显色剂二苯碳酰二肼反应，生成 紫红色化合物。
B.
酸性溶液中， Cr 6+ 与显色剂二苯碳酰二肼反应，生成苯肼羰基偶氮苯。
C.
当水样中存在亚铁和亚硫酸钠、硫化物时，可采取调节水样 PH=8 方法消除。
D.
此反应是在碱性溶液中进行的，最大吸收波长为 540nm 。
【简答题】What hazard may lie in the process of adjustments taken by export-relied countries?
【单选题】What we need to do for the Chinese civilization is not to lie on past glories, but to ________ and around. [ ]
A.
look forward
B.
look up
C.
look ahead
D.
look into
【单选题】____________ honest the boy was! All the students told a lie ____________ him.
A.
How; besides
B.
What an; except
C.
How; except
D.
What; besides
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