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【单选题】
化学实验的“目的一操作一现象一结论”是实验过程中几个相关的环节．下列关于实验过程的描述正确的是（ ） 实验过程 组别 实验目的 所加试剂 （或操作） 实验现象 实验结论 A 检验稀盐酸和氢氧化钠溶液是否恰好完全反应 在反应后的溶液中滴加无色酚酞试液 无明显现象 恰好完全反应 B 除去KCl中的少量K 2 CO 3 稀盐酸 有气泡产生 K 2 CO 3 已被除完 C 区分硬水和蒸馏水 肥皂水 产生大量泡沫 该液体为蒸馏水 D 用排空气法收集氧气时检验集气瓶中氧气是否集满 将带火星的木条伸人瓶内 木条复燃 瓶内氧气已集满A.
A
B.
B
C.
C
D.
D
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【单选题】Passage 2 Some people believe that cigarette smoking is dangerous and should therefore be considered a health hazard . They want their governments to create anti-smoking programs. People differ as to ...
A.
jumping, running or climbing
B.
working, sleeping or resting
C.
using,smoking or eating
D.
washing,bathing or cleaning
【单选题】What have high．income countries done to smoking?
A.
Banned smoking in the public and reduced tobacco taxes．
B.
Banned public smoking and established tobacco taxes．
C.
Dropped smoking rates and banned smoking in public．
D.
Dropped smoking rates and lowered tobacco taxes．
【单选题】Where can a user find the System32 folder on a Windows Vista x64 system?（）
A.
C:///Windows/System32（x64）
B.
C:///Windows/System
C.
C:///Windows/System32
D.
C:///Windows（x64）/System32
【简答题】561-______72=561-（128□72） A-B-______=A-（______□C） 125×______-25×=（______□______）x （A+B）×______=______×C+______□C 102×______=______×50+______×50．
【单选题】A Brief History of American Anti-Smoking Campaigns The First Anti-Smoking Treatise Tobacco is a native American plant that was first used as a smoking substance in the religious ceremonies of Indian m...
A.
Y
B.
N
C.
NG
【单选题】Passage 2 Some people believe that cigarette smoking is dangerous and should therefore be considered a health hazard . They want their governments to create anti-smoking programs. People differ as to ...
A.
for smoking
B.
neither for nor against smoking
C.
against smoking
D.
either for or against smoking
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