什么叫最小控顶距？最小控顶距要满足哪几方面需要？

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     Last year,I lived in Chile for half a year. I lived with a Chilean family and had the responsibilities of any Chilean teenager. I had good days and bad days I didn't understand.

     Chuquicamata,my host community,is a mining camp. When I arrived there,I was scared. It was so

different from what I was used to. There were lots of dogs on the streets,and there was no downtown,few smoothly paved streets,and little to do for entertainment. Rain was not seen very often,earthquakes and

windstorms were frequent.

     I had studied Spanish for two and a half years and was always one of the best students in my class. But in my first week in Chile I was only able to communicate and needed one person to whom I could explain my shock. I couldn't speak the thoughts in my head and there were so many.

     Most exchange students experience this like me. Culture shock presents itself in everything from

increased aggression towards the people to lack of appetite (食欲)．I was required to overcome all

difficulties.

     As time passed,everything changed. I began to forget words in English and to dream in Spanish and

love Chilean food. I got used to not depending on expensive things for fun. Fun in Chuquicamata was being with people. And I took math,physics,chemistry,biology,Spanish,art,and philosophy.

     But the sacrifices were nothing compared to the gain. I learned how to accept and to succeed in

another culture. I now have a deeper understanding of both myself and others.

1. The author came to Chile last year with the purpose of  ________.

A. paying a visit to Chile as a tourist

B. experiencing Chilean life as a teacher

C. studying Chilean culture as a college student

D. studying knowledge as an exchange student

2. On arriving in Chile,why did the author feel frightened?

A. Because he did not know how to get along with the local people.

B. Because it was full of dangers like earthquakes and windstorms.

C. Because its living conditions were worse than what he was used to.

D. Because it was not convenient for him to shop there.

3. In the first week in Chile the author  ________.

A. was not used to eating Chilean food

B. had some friends to have a chat with

C. couldn't communicate with people

D. couldn't express his thoughts in English

4. What did the author most probably think of his life in Chile?

A. Wonderful and worthwhile.

B. Difficult but meaningful.

C. Difficult and meaningless.

D. Boring and disappointing.

5. According to the passage,which of the following statements about Chile is TRUE?

A. Its official language is Spanish and English.

B. It is a developing country without foreign students.

C. It seldom rains and natural disasters often happen.

D. Most Chileans are not friendly to foreigners.

下列疾病不是由输血传染的是（）

A.巨细胞病毒感染

B.回归热

C.黑热病

D.疟疾

E.猫抓热

下列具有抒情诗、风景画特色的散文集是冰心的《（）》。

无《药品经营企业许可证》从事进口药品国内销售的属于

A．药品流通渠道混乱问题
B．药品分类管理问题
C．无证经营药品问题
D．药品不良反应问题
E．药品审批问题

特种作业操作证不需要进行复审。