有机残体的C/N为（）时，最宜于分解，大于此值时，容易出现（）现象；小于此值时，容易

请根据短文回答问题。

      Last week, Mrs. Black went to Beijing. She didn't know Beijing very well, and she lost her way. Suddenly

she saw a young man near a bus stop. She went up to the young man and said, " Excuse me! Can you tell me

the way to the Beijing Hotel, please? " The young man smiled. He didn't know Chinese! He came from Japanese.

But then he put his hand into his pocket, and took out a Chinese dictionary. He looked up some words. Then he

said slowly, " I'm sorry. I can't understand you. I do not speak Chinese. I am a Japanese."

1. When did Mrs. Black go to Beijing?

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2. Does she know Beijing very well?

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3. Where did she see a young man?

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4. Can the young man speak Chinese?

________________________________________________________________

5. Where does the young man come from?

________________________________________________________________

两性霉素B注射液遇氯化钠输液析出沉淀，其原因是（）

A.pH值改变

B.离子作用

C.溶剂组成改变

D.盐析作用

E.直接反应

分体壁挂式空调器安装时室内机高度以紧贴屋顶为佳。

我国最大的林区是 。

A．东北林区

B．西南林区

C．东南丘陵林区

D．“三北”防护林区

使用防冻液时，防冻液的冰点和使用地区的最低温度相同即可。