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【单选题】
在数据库的三级模式结构中，描述数据库中全体数据的全局逻辑结构和特性是( )?A.
用户模式
B.
逻辑模式
C.
外模式
D.
内模式
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【简答题】How can we get rid of garbage? Do we have enough energy sources to meet our future energy needs? These are two important questions that many people are asking today. Some people think that man might b...
【简答题】"七月流火”指天气（）。
【简答题】2002年我国制定新的结核病分类标准,将肺结核分为5种类型_________、__________、 ________、________和 _________ 。
【单选题】Passage Three How can we get rid of garbage.9 Do we have enough energy sources to meet our future energy needs? These are two important questions that many people are asking today. Some people think t...
A.
The shortage of energy and air pollution.
B.
The shortage of energy and the land to hold garbage.
C.
Air pollution and the shortage of fossil fuel.
D.
Air pollution and the shortage of land to hold garbage.
【单选题】How can we get rid of garbage? Do we have enough energy sources to meet our future energy needs? These are two important questions that many people are asking today. Some people think that man might b...
A.
The shortage of energy and air pollution.
B.
The shortage of energy and the shortage of empty land for holding garbage.
C.
Air pollution and the shortage of empty land for holding garbage.
D.
Air pollution and the shortage of fossil fuel.
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