问题 单项选择题

奈奎斯特定理描述了有限带宽、无噪声信道的最大数据传输速率与信道带宽的关系。对于二进制数据,若信道带宽B=3000Hz,则最大数据传输速率为______。

A.300bps

B.3000bps

C.6000bps

D.2400bps

答案

参考答案:C

解析:
[知识点] 数据通信技术基础
[评析] 奈奎斯特准则指出:信号在无噪声的信道中传输时,对于二进制信号的最大数据传输率Rmax与通信信道带宽B(B=f,单位是Hz)的关系可以写为: Rmax-2*f(bps)对于二进制数据,若信道带宽B=f=3000Hz,则最大的数据传输速率为6000bps。

阅读理解

My boss’s daughter was studying in the Philippines. He asked me if my husband and I could take care of her. He thought his daughter would be able to improve her English communication skills in this way.

After days of thinking, we agreed. He then brought her here and left after 3 days. I thought that my boss’s daughter was well-mannered, but that was wrong.

After a month of staying in the Philippines, she started to show her true colors. When my husband asked her what she wanted for breakfast, she answered him in a rude way. From then on, we experienced fights at home. There was a time when we didn’t talk to her for a week as a punishment of not being good to us. What I hated most was that she didn’t care about other people’s feelings. She ate ahead of us when we were still working and didn’t leave anything for us. So we had to separate her food from ours to avoid such a problem.

The worst thing about her was that she shouted at us. I was wondering if she did this to her parents. We told this to her parents, but unfortunately I didn’t think that solved the problem. This situation lasted for almost 8 months. Our patience was tested during that time.

We tried to teach her everything we could to make her a better person, but I guess 8 months may not to be enough. We even tried to understand her and adjust for her, but it didn’t work. I just hope that she learned something from us and from other Filipinos.

小题1:This passage is mainly about the writer’s experience of              .

A.trying to please her boss

B.changing a girl’s bad behavior

C.improving her communication skills

D.dealing with a teenage girl staying in her house小题2:Why did the boss want his daughter to stay with the writer ?

A.Because he was too busy to take care of his daughter

B.Because he wanted his daughter to take a holiday there

C.Because he wanted his daughter to improve her English in this way

D.Because he wanted the writer to teach his daughter good manners .小题3:What do the examples in paragraph 3 tell us ?

A.The daughter wasn’t behaving well.

B.The writer and her husband were careless.

C.The writer and her husband hated children.

D.The daughter tried her best to make others happy.小题4:The underlined word “that” in paragraph 4 refers to               .

A.being patient with her

B.her parents punishing her

C.asking her parents about her

D.telling her parents about her behavior小题5:After reading the passage , we learn that               .

A.the writer had known the daughter was hard to deal with

B.the daughter learnt to behave well in the end

C.the writer didn’t enjoy the daughter’s stay

D.the daughter hated dealing with others

多项选择题