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问题 单项选择题

国家对从事建筑活动的单位推行质量体系认证制度，建筑业企业根据（）原则可以向获得国家认可的认证机构申请质量体系认证。

A．自愿的

B．强制的

C．经济性

D．是否有利

答案

参考答案：A

听力题

根据短文内容和所给中文提示，写出空白处各单词的正确形式，每空限填一词。(10分)

There is a saying “Time is life and when the lazy man kills time ,he kills 小题1:_______ (他自己).”But today I did a 小题2:____( 愚蠢的)thing to 小题3:______（浪费)  a lot of time. This morning, after I had breakfast 小题4:______(迅速地 ).I watched TV. But it was too boring. Then I started to play computer games. I spent lots of time 小题5:______(玩）it. When I 小题6:______( 意识到 ) I should study hard for my coming English and math 小题7:_______( 考试 ).Four hours had passed, what should I do? I didn’t have 小题8: ______(足够的) time. Mum knew this and told me, “It’s not 小题9:_______(有帮助的) to be worried now. The only thing you can do is to do it at once. Don’t play again.” Mum’s words reminds me. I think Mom is right. I should be the 小题10:_____(所有者)of time and can’t make time fly away me.
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不定项选择

氦氖激光器能产生三种波长的激光，其中两种波长分别为λ1=0.632 8μm，λ2=3.39μm，已知波长为λ1的激光是氖原子在能级间隔为△E1=1.96 eV的两个目能级之间跃迁产生的。用△E2表示产生波长为λ2的激光所对应的跃迁的能级间隔，则△E2的近似值为[ ]

A.10.50 eV

B.0.98 eV

C.0.53 eV

D.0 36 eV

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