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问题 解答题

圆柱的侧面展开图形有可能是梯形．______． （判断对错）

答案

因为，把一个圆柱沿高剪开，当圆柱的底面周长等于圆柱的高时，展开的图形是正方形；

当圆柱的底面周长不等于圆柱的高时，展开的图形是长方形；

当把一个圆柱不是沿高剪开，而是斜着剪开，得到的图形是平行四边形，

所以，将圆柱的侧面展开有可能是长方形，也有可能是正方形，还有可能是平行四边形，不可能是梯形．

故答案为：×．

补全对话，情景问答

根据语境。填人适当的词语或句子补全对话。

A: Where are you from?

B: I'm from Korea.

A: What are 1.            manners in your country?

B:  Korea is a country famous for its many native dishes.  2.           food is rich in nutrition, well-balanced

and low in calories.  They say that you can eat as much Korean food as you like and never gain weight.

A:  Wonderful.  I eat 3.           .  I like to eat nice things and keep slim at the same time,

B: Come to Korea then.

A: Is Korean food chiefly made of 4.           ?

B: Yes, it is. Seasonings include garlic, red peppers, scallions, soy saucey fermented bean paste, ginger

and sesame oil.

A: 5.           . the old or the young?

B: Of course, the oldest eat first.  They are respected most in our country.
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单项选择题

难度P值越接近于O或接近于1，越无法区分被试者之间能力的差异。相反，P值越接近于0.50，区别力越高。为了使测验具有更大的区别力，应选择难度在0.50左右的试题比较合适，各题难度应在( )之间。

A．0.50±0.10
B．0.50±0.20
C．0.50±0.30
D．0.50±0.40
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