LDH是由几个亚基组成的（）。A.2个 B.3个 C.4个 D.5个 E.6个

阅读选择。

Here is Ben's wallpaper for his class. It is not finished, but we can still have a quick look at it.

1. Which flag does Ben need? [ ]

A.

B.

C.

D.

2. In the park, we shake hands with a man who we meet for the first time in ____.[ ]

A. New Zealand and Brazil.

B. Brazil and Japan.

C. Japan and New Zealand.

D. Brazil, Japan and New Zealand.

3. In New Zealand, two new friends press their noses together because ____. [ ]

A. the two men meet each other for first time.

B. they are probably greeting in the Maori way.

C. it is the special way of greeting in their country.

D. they want to show their interest and friendliness.

4. While travelling, a Japanese passenger beside you is always smiling with his eyes closed.You may

    think ____. [ ]

A. he is showing politeness to you.

B. he wants to make friends with you.

C. he is feeling very embarrassed.

D. he is thinking about something funny

5. Which title may Ben use? [ ]

A. World Greetings

B. Making Friends

C. Shaking Hands

D. World Meetings

—Can you tell me who        the telephone?  

—Alexander Graham Bell.[ ]

A. invented              

B. discovered  

C. created                

D. found

不属于公钥加密算法的是( )。

A．DSS

B．RSA

C．MD5

D．E1gamal

至20世纪初，“外货风行，土布渐归淘汰”，洋布战胜土布，主要原因是

A．洋布外观漂亮

B．洋布广告充斥

C．洋布引领时尚

D．洋布物美价廉

观察者从前往后看，在正立投影面上得到物体的正面投影叫做主视图。