问题 单项选择题

如果在通信信道上传送1比特信号所需要的时间是0.001ps,那么信道的数据传输速率为______。

A.1 Mbps

B.10Mbps

C.100Mbps

D.1Gbps

答案

参考答案:D

解析: 本题考查点是信道数据传输速率的计算。信道的数据传输速率是指每秒可以传输的二进制代码位数,单位是“位/秒”,记作bps或b/s,因此,数据传输速率又称为比特率。若通信信道上传送1比特信号所需要的时间是0.001μs,即10-9s,那么信道的数据传输速率应该为109 bps,即 1Gbps。

阅读理解

(共5小题,每小题2.5分,满分12.5分)

根据对话内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

Taking good notes is a time-saving skill that will help you to become a better student in several ways.      1    .Second, your notes are excellent materials to refer to when you are studying for a test. Third, note-taking offers variety to your study time and helps you to hold your interest.

You will want to take notes during classroom discussions and while reading a textbook or doing research for a report. ____2_____. Whenever or however you take notes, keep in mind that note-taking is a selective process._____3______.

The following methods may work best for you.                                

●Read the text quickly to find the main facts and ideas in it.

●Carefully read the text and watch for words that can show main points and supporting facts.

●Write your notes in your own words.

●_____4_____.

●Note any questions or ideas you may have about what was said or written.

As you take notes, you may want to use your own shorthand(速记). When you do, be sure that you understand your symbols and that you use them all the time._____5_____.

A.Use words , not complete sentences.

B.There are three practical note-taking methods.

C.You must write your notes on separate paper.

D.Otherwise, you may not be able to read your notes later.E. You will also want to develop your own method for taking notes.

F. That means you must first decide what is important enough to include in your notes.

G. First, the simple act of writing something down makes it easier for you to understand and remember it.

单项选择题