用一个平面去截正方体,所得的截面不可能是[ ] A. 六边形 B. 菱形 C.

题型:选择题

问题:

用一个平面去截正方体,所得的截面不可能是[ ]

A. 六边形

B. 菱形

C. 梯形

D. 直角三角形

考点:柱、锥、台、球的结构特征
题型:选择题

Mary will ever forget the first time she saw him. He suddenly appeared in class one day ,   16  (wear) sun glasses . He walked in as if he    17  (buy) the school ,And the word quickly got around that he was from New York City .

For some reason he sat beside Mary. Mary felt    18  (please), because there were many empty seats in the room .But she quickly realized that it wasn’t her, it was probably the fact that she sat in    19  last row.

   20   he thought he could escape attention by sitting at the back, he was wrong. It might have made it a little    21  (hard) for everybody because it meant they had to turn around, but that didn’t stop the kids in the class. Of course whenever they turn to look at him, they had to look at Mary ,   22   made her feel like a star .

“Do you need those glasses for medical reasons ?” the teacher asked .The new boy shook his head .”Then I’d appreciate it if you didn’t wear them in class .I like to look at your eyes when I’m speaking to you.” The new boy looked at the teacher    23   a few seconds and all the other students wondered    24   the boy would do .Then he took    25   off , gave a big smile and said “That is cool.”

题型:选择题
已知正方形ABCD边长为1,一只蚂蚁在此正方形区域内随机爬行,则它在离顶点A的距离小于1的地方的概率为(  )
A.
π
2
B.
π
4
C.
π
6
D.
π
8
题型:选择题

在一棵二叉树上第5层的结点数最多是( )。

A.8

B.16

C.32

D.15

题型:选择题

下列哪项可见尿后余沥()

A.肾精不足

B.肾阴亏虚

C.瘀血内阻

D.肾阳不足

E.肾气虚弱

题型:选择题

水的化学耗氧量代表

A.水体中可被氧化的有机物的总量

B.水体中可被氧化的无机物的总量

C.水体中氧化和还原性有机物的总量

D.水体中可被氧化的有机物和还原性无机物的总量

E.水体中有机物的总量

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