关系规范理论是关系数据库进行逻辑设计的基础,这个理论最基本的要求是关系中的每个属性是

题型:单项选择题

问题:

关系规范理论是关系数据库进行逻辑设计的基础,这个理论最基本的要求是关系中的每个属性是( )。

A.类型不变的
B.宽度不变的
C.不可分割的
D.互不相关的

考点:计算机等级考试VISUALFOXPRO二级VISUALFOXPRO笔试
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不属于血细胞分析仪红细胞参数的是 ()

A.HGB

B.RDW

C.MPV

D.Hct

E.MCH

题型:单项选择题

阅读理解。

     I was concentrating on my work when my friend called me saying he was coming to visit me. After

explaining where my new house was, I told him that I had left the key under the doormat, which helps

preventing the floor from being dirty. Since I knew it would be quite late before I could get back, I suggested

that he make himself at home and help himself to anything that was kept in the refrigerator(冰箱). 

     Two hours later my friend phoned me from the house. At the moment, he said he was listening to some

of my records after having had a nice meal. He had found the pan and meat in the refrigerator. Now, he was

drinking a cup of tea and hoped that I would join him soon. When I asked him if he had any difficulty finding

the house, he answered that the only problem was that he had not been able to find the key under the doormat,

but luckily, the living room window by the apple tree had been left open and he had climbed in through the

window. I listened to all this in great surprise. There is no apple tree outside my window, but there is one by

the living room window of my next-door neighbor's house!

1. When my friend arrived, I could not go to meet him because________.

A. we were not good friends

B. I was busy at work

C. he had not told me that he would come

D. I did not want to see him

2. A doormat is a mat (垫子)______.

A. used as a door

B. for cleaning the bottom of shoes

C. put up on a door as an ornament(装饰物)

D. near a door under which people put their keys

3. I listened to my friend's phone call in great surprise because____.

A. he had not waited for me to eat together  

B. he had eaten too much of the food

C. he mistook my neighbor's house for mine  

D. he had left the house with the window open

4. At last my friend______.

A. did not enter my house  

B. entered my house after he opened the door  

C. entered my house by climbing through the window

D. entered my house with the help of my neighbor

题型:单项选择题

何谓减压病?如何治疗?

题型:单项选择题

捞渣机共有()个中间导向轮。

A、4

B、6

C、8

D、10

题型:单项选择题

食物中蛋白质进入体内后最终的代谢产物是()。

A.氨基酸

B.尿素

C.肌酐

D.尿酸

E.核糖核酸

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