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问题 选择题

假设有三个细胞液浓度不同的细胞，放在某浓度的蔗糖溶液中出现如图所示状态，你认为这三个细胞在未发生上述情况之前，其细胞液浓度依次是

[ ]

A．A<B<C

B．A>B>C

C．B>A>C

D．B<A<C

答案

答案：B

推断题

已知：

水杨酸酯E为紫外吸收剂，可用于配制防晒霜。E的一种合成路线如下：

 

请回答下列问题：

（1）一元醇A中氧的质量分数约为21.6%。则A的分子式为         ；结构分析显示A只有一个甲基，A的名称为           。

（2）B能与新制的Cu(OH)2发生反应，该反应的化学方程式为           。

（3）C有    种结构；若一次取样，检验C中所含官能团，按使用的先后顺序写出所用试剂     ；

（4）第③的反应类型为         ；D所含官能团的名称为        。

（5）写出同时符合下列条件的水杨酸所有同分异构体的结构简式：     。

A、分子中含有6个碳原子在一条线上         

B、分子中所含官能团包括水杨酸具有的官能团

（6）第④步的反应条件为          ；写出E的结构简式          。
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单项选择题

Proper arrangement of classroom space is important to encouraging interaction. Most of us have noticed how important physical setting is to efficiency and comfort in our work. College classroom space should be designed to encourage the activity of critical thinking. We may be approaching the twenty-first century, but step into almost any college classroom and you step back in time at least a hundred years. Desks are normally in straight rows, so students can clearly see the teacher but not all their classmates. The assumption behind such an arrangement is obvious. Everything of importance comes from the teacher.
With a little imagination and effort, unless desks are fixed to the floor, the teacher can correct this situation and create space that encourages interchange among students. In small or standard-size classes, chairs, desks, and tables can be arranged in a variety of ways. The primary goal should be for everyone to be able to see everyone else. Larger classes, particularly those held in lecture halls, unfortunately, allow much less flexibility.
Arrangement of the classroom should also make it easy to divide students into small groups for discussion or problem-solving exercises. Small classes with movable desks and tables present no problem. Even in large lecture halls, it is possible for students to turn around and form groups of four to six. Breaking a class into small groups provides more opportunities for students to interact with each other, think out loud, and see how other students’ thinking processes operate all essential elements in developing new modes of critical thinking. In courses that regularly use a small group format, students might be asked to stay in the same small groups throughout the course. A colleague of mine, John, allows students to move around during the first two weeks, until they find a group they are comfortable with. John then asks them to stay in the same seat, with the same group, from that time on. This not only creates a comfortable setting for interaction but helps him learn students’ names and faces.

The greatest advantage in allowing each student to find his own group might be that ______.

A. the teacher saves the trouble in doing that
B. learning is made comfortable in this way
C. the teacher can easily remember students’ names and faces
D. brighter students can help slower ones
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