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B.M.Trost1991年提出了原子经济的概念:若所有反应物均全部转化为欲得的产物，则此反应就是100%的原子经济反应。对于加成、取代和消去三种反应类型而言，其中最具有原子经济反应潜力的应是_______反应。

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既能与盐酸反应，又能与氢氧化钠溶液反应的单质是

A. S
B. Fe
C
D. A1

《课程标准》也对高中语文教学提出了更高的要求，较之义务教育阶段的课程目标，可以发现高中语文教学有这样几个提升：()

A. 加强语文学习的综合性，注重“积累”基础上的“整合”
B. 在“感受”基础上加强“鉴赏”，这意味着阅读文学作品，不能止于感性的、对内容的感受，而是要递升到分析、批评的高度，注意形式的鉴赏
C. “思考·领悟”、“应用·拓展”、“发现·创新”等目标，体现了高中语文学习的“探究”品位，因此，教学中应该有更多的研究性学习、多元解读、文化探究的成分
D. 强调“发展独立阅读的能力”，众多文本不应再过多依赖教师亦步亦趋的教读，而是要敢于放手，给学生充分的自读时间，以有效的手段激发学生自主阅读的兴趣、保证自主阅读的质量。
E. 对众多教学内容做出适当整合

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—定质量的理想气体经历压强增加的过程，若在此过程中

A. 气体的体积减小，则温度一定降低
B. 气体的体积保持不变，则温度可能不变
C. 气体的体积增大，则温度一定升高
D. 气体的体积增大，则温度可能不变

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阅读理解：阅读下面的短文，根据文章内容从A、B、C三个选项中选出一个最佳选项。
The houses we live in are very {A. expensiveB、B. importantB、C. huge}. They keep us from being cold in the winter and hot in the summer. In the winter they keep out of the snow. They also keep out the wind. Even if it is blowing outside, we are nice and warm inside. In the summer houses keep the hot sun from us. When it rains, they keep us from getting wet.
Houses are also places {A. whichB、B. thatB、C. where} we feel safe. People can’t get at us or our things. Houses give us a place to be together with our families and friends. Mothers and fathers {A. care forB、B. care aboutB、C. take care} their children there. The children play there. The family eat and sleep under the same roof.
Houses are different in many ways. They are made of different things. Some houses are made of wood. Some are made of stones. Sometimes more than one thing is used to make a house.
Houses come in different {A. placesB、B. sizesB、C. names}. Some houses have only one room. Some houses have more than one room. Big buildings found in cities have a great many rooms. They hold many families. The rooms in which each family lives are called an apartment.
Houses are different in the ways they are {A. buildB、B. buildingB、C. built}. Houses in tropic countries can be lightly built. In places where it rains much of the time, houses must keep out the water.
take care (“注意”，“当心”，“留心”)

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