袋中有40个小球，其中红 * * 16个、蓝 * * 12个，白 * *

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问题选择题

袋中有40个小球，其中红 * * 16个、蓝 * * 12个，白 * * 8个，黄 * * 4个，从中随机抽取10个球作成一个样本，则这个样本恰好是按分层抽样方法得到的概率为（　　）

A．

312

416

1040

B．

312

416

1040

C．

112

416

1040

D．

412

216

1040

答案

∵这个样本要恰好是按分层抽样方法得到的概率

依题意各层次数量之比为4：3：2：1，

即红球抽4个，蓝球抽3个，白球抽2个，黄球抽一个，

根据古典概型公式得到结果为

312

416

1040

；

故选A

单项选择题 A3/A4型题

上皮组织由密集排列的细胞和极少量的细胞间质构成，细胞有明显的极性，有丰富的神经末梢，但无血管和淋巴管。上皮组织主要分为被覆上皮和腺上皮，具有保护、分泌、吸收和排泄等功能。被覆上皮覆盖于身体表面和衬贴在有腔器官的腔面。

下列叙述正确的是（）

A.单层扁平上皮分布于肾小管、胆小管等处

B.单层立方上皮分布于心、血管、淋巴管内表面

C.单层柱状上皮分布于胃、肠等消化道黏膜

D.变移上皮分布于皮肤的表皮、口腔、食管

E.假复层纤毛柱状上皮分布于胸膜、腹膜、心包膜

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写作题

第二节：读写任务（共1小题，满分 25分）

阅读下面的一封信，然后按照要求写一篇150词左右的英语短文。

Recently I took part in an English speech contest and successfully went into the final. That day, I thought I had done a good job. At that moment I even had a strong feeling of being the champion. But my dream was soon shattered when my final score was announced. I stood in the hall, feeling empty-minded and puzzled. My memory went back to when I was in junior middle school. I took part in a similar speech contest. I was too proud of myself. I was not well prepared, so it ended up as a total failure. But this time should be different! I had spent a lot of time tailoring each word. Why was it all in vain and I had to be a loser again? Very frustrated, I swore not to take part in this kind of competition again.

I was just about to leave when a well-known TV host suddenly said to me he did appreciate my speech. On hearing this, I was filled with mixed feelings---partly surprised, partly excited, partly sad, but there was one thing I am certain about---I did feel something warm and comforting floating inside my body. I never knew a few words and a kind smile could be so inspiring that I suddenly realized that frustration, sorrow, happiness and inspiration are treasures to make life more meaningful. It is these elements that make life real.

【写作内容】

1. 以约30词概括原文的内容要点；

2. 以约120词描写一次你失败的经历，至少包含以下的内容要点：

a) 叙述你曾经经历的一件失败的事；

b) 因事情的结果导致的当时的心情；

c) 最后自己的感悟。

【写作要求】

(1) 你可以使用实例或自行组织故事，也可以参照阅读材料的内容，但不要抄袭阅读材料中的句子； (2) 标题自定。

【评分标准】概括准确，语言规范，内容合适，篇章连贯。

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