西安交大网络教育秋操作系统原理在线作业习题答案100分

西交《操作系统原理》在线作业一、单选题（共 30 道试题，共 60 分。

）1. 在下列文件的物理结构中，不利于文件长度动态增长的是（）、A. 连续结构B. 链接结构C. 索引结构D. Hash结构正确答案：A2. 通道是一种（）。

A. I/O设备B. 设备控制器C. I/O处理机D. I/O控制器正确答案：C3. 一个进程是（）。

、A. 由协处理机执行的一个程序B. 一个独立的程序+数据集C. PCB结构与程序和数据的组合D. 一个独立的程序正确答案：C4. 以下叙述中，不正确的是（）、A. 采用动态重定位，在必要时可以改变装入的作业在主存中的存放区域B. 采用动态重定位的系统支持“程序浮动”C. 采用静态重定位的系统不支持“程序浮动”D. 采用动态和静态重定位的系统都支持“程序浮动”正确答案：D5. 联想存储器在计算机系统中是用于（）、A. 存储文件信息B. 与主存交换信息C. 地址变换D. 存储通道程序正确答案：C6. 在页式存储管理中，假定地址用m个二进制位表示，其中页内地址部分占用了n个二进制位，那么最大的作业允许有（）个页面。

、A. 2nB. 2(m-n)C. 2mD. 2(m+n)正确答案：B7. 以下有关可变分区管理中采用的主存分配算法说法中错误的是（）、A. 可变分区管理采用的主存分配算法包括最先适应、最佳适应、最坏适应等算法B. 最先适应算法实现简单，但碎片过多使主存空间利用率低C. 最佳适应算法是最好的算法，但后过的较大作业很难得到满足D. 最差适应算法总是选择最大的空闲区用于分割，使得余下的分区仍可使用正确答案：C8. 银行家算法是一种（）算法。

、A. 死锁预防B. 死锁避免C. 死锁解除D. 死锁检测正确答案：B9. 下面关于索引文件的论述中，第（）条是正确的论述。

A. 索引文件中，索引表的每个表项中含有相应记录的关键字和存放该记录的物理地址。

B. 对顺序文件进行检索时，首先从FCB中读出文件的第一个盘块号；而对索引文件进行检索时，应先从FCB中读出文件索引表始址。

西交《计算机应用基础》在线作业100分答案试卷总分：100.测试时间：--。

试卷得分：100一、单选题（共?30?道试题，共?60?分。

）。

得分：601.超文本的含义是( )。

A.该文本中含有声音B.该文本中含有二进制数C.该文本中含有链接到其他文本的连接点D.该文本中含有图像答案:C满分：2分得分：22.已知英文字母m的ASCII码值为109，那么英文字母p 的ASCII码值为( )。

A。

111B。

112C。

111D。

112答案:B满分：2分得分：2专有的特点为( )。

A.采用TCP/IP协议B.接纳ISO/OSI树立7层和谈C.用户和应用程序不必了解硬件连接的细节D.接纳IEEE802和谈答案:A满分：2分得分：24.第二代计较机利用的电子元件是（）。

A.电子管B.晶体管C.集成电路D.超大规模集成电路答案:B满分：2分得分：25.以( )将网络划分为广域网(WAN)、城域网(MAN)和局域网( LAN )。

A.接入的计算机的数量的多少B.使用设备的多少C。

C、拓扑结构D.网络掩盖范围的大小答案:D满分：2分得分：26.在IE欣赏器拜候FTP效劳器时，以下地址中属于有用的FTP地址花式的是( )。

A。

B。

XXXD。

答案:A满分：2分得分：27.在Windows中，某个窗口的标题栏的右端的三个图标可以用来( )。

A.使窗口最小化、最大化和改变显示方式B.改变窗口的颜色、大小和背景C.改变窗口的大小、形状和颜色D.最小化、最大化(向下还原)和关闭窗口答案:D满分：2分得分：28.保障信息安全最基本、最核心的技术措施是( )。

A.数据加密技术B.信息确认技术C.网络控制技术D.反病毒技术答案:A满分：2分得分：29.XXX?XXX计较机的根本原理是( )。

A.程序外接B.逻辑连接C.数据内置D.程序存储答案:D满分：2分得分：210.Windows中系统还原程序的主要作用是( )。

A.可实现对系统的备份B.还原系统硬件和软件配置C.还原被破损的系统程序D.可根据需要还原故障前的系统答案:A满分：2分得分：211.以下( )不是搜索引擎的主要任务。

西安交通大学19年3月课程考试《操作系统原理》作业考核试题（含主观题）1、B2、A3、A4、B5、B一、单选题共10题，40分1、采用( )不会产生内部碎片。

A分页式存储管理B分段式存储管理C固定分区式存储管理D段页式存储管理正确答案是：B2、( )与设备独立性密切相关。

A设备的统一命名B中断处理C死锁避免D设备驱动程序正确答案是：A3、系统抖动现象的发生是由( )引起的。

A置换方法不当引起的B交换的信息量过大C内存容量不足D请求页式管理方案正确答案是：A4、UNIX系统把输入、输出设备看做( )A普通文件B特殊文件C目录文件D管道文件正确答案是：B5、下面( )算法适用于分时系统中的进度调度AFCFSB时间片调度C优先级调度算法D队列调度算法正确答案是：B6、解决死锁的途径是( )。

A立即关机再重新启动B立即关机排除故障C不要共享资源、增加独占资源D设计预防死锁方法，运行检测并恢复正确答案是：D7、两个进程合作完成一个任务,在并发执行中,一个进程要等待其合作伙伴发来信息或者建立某个条件后再向前执行,这种关系是进程间的( )关系。

A同步B互斥C竞争D合作正确答案是：A8、下面内存管理方法中有利于把程序动态链接的是( )。

A分段式存储管理B分页存储管理C可变分区分配D固定分区分配正确答案是：A9、CPU输出数据的速度远远高于打印机的打印速度,为解决这一矛盾,可采用( )。

A并行技术B通道技术C缓冲技术D虚存技术正确答案是：A10、在多道程序环境下,操作系统以( )作为资源分配的基本单元。

A作业B程序C进程D线程正确答案是：C二、判断题共5题，10分1、中断是现代操作系统实现并行性的硬件基础之一。

A对B错正确答案是：A2、DMA方式是一种完全由硬件执行I/O交换的工作方式。

A对B错正确答案是：A3、如果没有中断技术,那么多道程序设计就不可能实现。

A对B错正确答案是：A4、进程由进程控制块和数据集,以及对该数据进行操作的程序组成。

操作系统原理_西安交通大学中国大学mooc课后章节答案期末考试题库2023年1.操作系统的基本功能是（）。

答案:控制和管理系统内的各种资源2.系统调用的目的是（）。

答案:请求系统服务3.在中断发生后，进入中断处理的程序属于（）。

答案:操作系统程序4.当CPU处于核心态时，它可以执行的指令是（）。

答案:计算机中全部指令5.PCB是进程实体的一部分，下列（）不属于PCB。

答案:全局变量6.分时操作系统通常采用（）调度算法来为用户服务。

答案:时间片轮转7.在进程调度算法中，对短进程不利的是（）。

答案:先来先服务调度算法8.P、V操作实现进程同步，信号量的初值为（）。

答案:9.对于两个并发进程，设互斥信号量为mutex（初值为1），若mutex=-1则（）。

答案:表示有一个进程进入临界区，另一个进程等待进入10.有一个计数信号量S：若干个进程对S进行了28次P操作和18次V操作之后，信号量S的值为0，请问该信号量S原来的值是多少？答案:1011.信箱通信是一种（）通信方式。

答案:间接通信12.死锁预防是保证系统不进入死锁状态的静态策略，其决办法是破环产生死锁的四个必要条件之一，下列方法中破坏了“循环等待”条件的是（）。

答案:资源有序分配策略13.某系统中共有11台磁带机，X个进程共享此磁带机设备，每个进程最多请求使用3台，则系统不会死锁的X值是（）。

答案:514.一个进程在获得资源后，只能在使用完资源后由自己释放，这属于死锁必要条件的（）。

答案:不剥夺条件15.某段表的内容见下表，一逻辑地址为（2,154），它对应的物理地址为（）段表段号段首址段长度0 120K 40K1 760K 30K2 480K 20K3 370K 20K答案:480K+15416.多进程在主存中彼此互不干扰的环境下运行，操作系统是通过（）来实现的。

答案:内存保护17.（）存储管理方式提供一维地址结构。

答案:分页18.假设一个页式存储管理系统具有快表，多数活动页表项都可以存在其中。

138682--西安交通大学操作系统原理（高起专）期末备考题库138682奥鹏期末考试题库合集单选题：（1）下面（）种页面置换算法会产生Belady异常现象？A.先进先出页面置换算法（FIFO）B.最近最久未使用页面置换算法（LRU）C.最不经常使用页面置换算法（LFU）D.最佳页面置换算法（OPT）正确答案：A（2）使用户所编制的程序与实际使用的物理设备无关是由（）功能实现的。

A.设备分配B.缓冲管理C.设备管理D.设备独立性正确答案：D（3）在请求调页系统中有着多种置换算法：选择最先进入内存的页面予以淘汰的算法称为（）。

A.FIFO算法B.OPT算法C.LRU算法D.NRU算法正确答案：A（4）通常，文件的逻辑结构中（）组织方式，既适合于交互方式应用，也适合于批处理方式应用。

A.堆文件B.流式文件C.索引顺序文件D.顺序文件正确答案：C（5）从总体上说，多道程序设计技术可（）单位时间的算题量。

A.增加B.减少C.维持正确答案：A（6）从静态角度看，进程由程序、数据和（）三部分组成。

A.JCBB.DCBC.PCBD.PMT正确答案：C（7）在I/O设备控制的发展过程中，最主要的推动因素是（）、提高I/O速度和设备利用率。

A.提高资源利用率B.提高系统吞吐量C.减少主机对I/O控制的干预D.提高CPU与I/O设备的并行操作程度正确答案：C（8）为了实现多道程序设计，计算机需要有（）。

A.更大的内存B.更快的外部设备C.更快的CPUD.更先进的终端正确答案：A（9）在一单处理机系统中，若有5个用户进程，在非管态的某一时刻，处于阻塞态的用户进程最多有（）个。

A.1B.2C.3D.5正确答案：D（10）下列第（）项不是文件系统的功能?A.文件系统实现对文件的按名存取B.负责实现数据的逻辑结构到物理结构的转换C.提高磁盘的读写速度D.提供对文件的存取方法和对文件的操作正确答案：C（11）操作系统中，进程与程序的重要区别之一是（）。

2017年秋《计算机网络原理》习题答案一、单项选择题（本大题共50小题，每小题2分，共100分）1、域名与IP地址的关系是（B）。

A、一个域名对应多个IP地址B、一个IP地址对应多个域名C、域名与IP地址没有任何关系D、一一对应2、域名系统DNS的作用是（B）。

A、存放主机域名B、将域名与IP地址进行转换C、存放IP地址D、存放电子邮箱号3、E-mail地址格式正确的表示是（D）。

A、主机地址@用户名B、用户名，用户密码C、电子邮箱号，用户密码D、用户名@主机域名4、如果用户应用程序使用UDP协议进行数据传输，那么下面哪一部分程序必须承担可靠性方面的全部工作？（D ）A、数据链路层程序B、互联网层程序C、传输层程序D、用户应用程序5、属于网络115. 17.200.0/21 的地址是( B )。

A、115.17.198.0B、115.17.206.0C、115.17.217.0D、115.17.224.06、在OSI 参考模型中，上层协议实体与下层协议实体之间地逻辑接口叫做服务访问点（SAP）。

在Internet中，网络层地服务访问点是( C )。

A、MAC 地址B、LLC 地址C、IP 地址D、端口号7、在Internet上有许多协议，下面的选项中能够正确表示协议层次关系地是( A )。

8、内部网关协议RIP 是一种广泛使用的基于( B )的协议。

RIP 规定一条通路上最多可包含的路由器数量是( B )。

（1）A．链路状态算法B．距离矢量算法C．集中式路由算法D．固定路由算法（2）A．1个B．16个 C．15个 D．无数个9、在CSM A/CD以太网中，如果有5个站点都要发送数据，其中某个站点发现信道空闲，它就立即发送数据。

那么（C）A、本次发送不会产生冲突B、本次发送必然产生冲突C、本次发送可能产生冲突D、次发送产生冲突的概率为0.210、以下哪一条要求不是全双工以太网运行的必要条件？（B）A、发送和接收信道应该使用分离的网络介质。

第一章操作系统引论1. 设计现代OS的主要目标是什么?方便性，有效性，可扩充性和开放性.2. OS的作用可表现为哪几个方面?a. OS作为用户与计算机硬件系统之间的接口；b. OS作为计算机系统资源的管理者；c. OS实现了对计算机资源的抽象.7. 实现分时系统的关键问题是什么?应如何解决?a. 关键问题：使用户能与自己的作业进行交互，即当用户在自己的终端上键入命令时，系统应能及时接收并及时处理该命令，再将结果返回给用户。

b. 解决方法：------对于及时接收，只需在系统中设置一多路卡，使主机能同时接收用户从各个终端上输入的数据；此外，还须为每个终端配置一个缓冲区，用来暂存用户键入的命令（或数据）。

------对于及时处理，应使所有的用户作业都直接进入内存，并且为每个作业分配一个时间片，允许作业只在自己的时间片内运行，这样在不长的时间内，能使每个作业都运行一次。

12. 试在交互性，及时性和可靠性方面，将分时系统与实时系统进行比较.a. 分时系统是一种通用系统，主要用于运行终端用户程序，因而它具有较强的交互能力；而实时系统虽然也有交互能力，但其交互能力不及前。

b. 实时信息系统对实用性的要求与分时系统类似，都是以人所能接收的等待时间来确定；而实时控制系统的及时性则是以控制对象所要求的开始截止时间和完成截止时间来确定的，因此实时系统的及时性要高于分时系统的及时性。

c. 实时系统对系统的可靠性要求要比分时系统对系统的可靠性要求高。

13. OS具有哪几大特征?它的最基本特征是什么?a. 并发性、共享性、虚拟性、异步性。

b. 其中最基本特征是并发和共享。

（最重要的特征是并发性）18. 是什么原因使操作系统具有异步性特征?在多道程序环境下允许多个进程并发执行，但由于资源等因素的限制，进程的执行通常并非一气呵成，而是以走走停停的方式运行。

内存中的每个进程在何时执行，何时暂停，以怎样的速度向前推进，每道程序总共需要多少时间才能完成，都是不可预知的，因此导致作业完成的先后次序与进入内存的次序并不完全一致。

西安交大网络教育2017年秋《英语(四)》在线作业习题答案100分一、选择题1. It was getting _______ , he had to stop to have a rest.A. very darkerB. dark and darkC. darker and darkerD. darkest and darkest2. The film brought the hours back to me A I was taken good care of in that remote village.A. whenB. whereC. thatD. until3. As the busiest woman there, she made _________her duty to look after all the other people's affairs in that town.A. thisB. thatC. oneD. it4. It's high time that he settled down in the country and B a new life.A. startB. startedC. startingD. to st5．I won’t make the ___mistake next time.A. likeB. sameC. nearD. similar6.----She has two best friends.----___of them is in the country.A. AllB. BothC. No oneD. Neither7. This overcoat cost ________. What's more, they are _________small for me.A. very much; veryB. too much; much tooC. much too; too muchD. very much; too much8. — Did the medicine make you feel better?— No. The more ________, ___________ I feel.A. medicine I take; and the worseB. medicine I take; the worseC. I take medicine; the worseD. I take medicine; worse9．一Haven’t seen you for ages!What are you busy doing now?一A．1 hate the weather here．B．My hair is getting a bit longer．C．Yeah，thanks for coming．D．I am working part time in a bookshop，you know．10．—Thanks for your help．—A．My pleasure．B．Never mind．C．Quite right．D．Don’t thank me11. The film brought the hours back to me I was taken good care of in that remote village.A. whenB. whereC. thatD. until 12．一Marilyn，I'm afraid I have to be leaving now．—A．That sounds wonderful．B．Oh，so early?C．Not at a11．D．Good luck!13 It is not until you have lost your health _________ you know its value.A. untilB. whenC. whatD. that14. It's high time that he settled down in the country and B a new life.A. startB. startedC. startingD. to start 15．一Paul，?一Oh，that’s my father! And beside him，my mother．A．what is the person over thereB．who’s talking over thereC．what are they doingD．which is that16．一Hi，Tom，how’s everything with you?—，and how are you?A．Don’t mention it B．Hmm, not too bad C．Thanks D．Pretty fast17.----The baby is hungry.----But there’s ___milk in the bottle.A. littleB. a littleC. fewD. a few18. Would you like something _________?A. drinkB. to drinkC. drinkingD. for drinking19. The wild flowers looked like a soft orange blanket _________ the desert.A. coveringB. coveredC. coverD. to cover20. _______ is the population of Paris?A. How manyB. How muchC. HowD. What21.----___is your girl friend like?----She is very kind and good-lookingA. HowB. WhatC. WhichD. Who 22．一That’s a beautiful dress you have on!—A．Oh，thanks．I got it yesterday．B．Sorry，it’s too cheap．C．You can have it．D．See you later．23. It is not until you have lost your health ___________ you know its value.A. untilB. whenC. whatD. that24. As the busiest woman there, she made _________her duty to look after all the other people's affairs in that town.A. thisB. thatC. oneD. it25. It was getting ________ , he had to stop to have a rest.A. very darkerB. dark and darkC. darker and darkerD. darkest and darkest26. — Did the medicine make you feel better?— No. The more ________, ___________ I feel.A. medicine I take; and the worseB. medicine I take; the worseC. I take medicine; the worseD. I take medicine; worseart27．一Why didn’t you come to my birthday party yesterday?一A．Excuse me，my friend sent me a flower．B．Fine，I never go to birthday parties．C．Ha…ha，I don’t like birthday parties．D．Sorry，but my wife had a car accident28．一Hi，welcome back!Had a nice trip?一A．Oh，fantastic!Fresh air，and sunshine every day．B．Come on．I’ve got lots of fun．C．By the way，I don’t like Saturdays．D．Well，I'll look forward to your phone call．29. The wild flowers looked like a soft orange blanket ________ the desert.A. coveringB. coveredC. coverD. to cover30. ________ is the population of Paris?A. How manyB. How muchC. HowD. What31. Would you like something ________?A. drinkB. to drinkC. drinkingD. for drinking32. This overcoat cost _______. What's more, they are ________small for me.A. very much; veryB. too much; much tooC. much too; too muchD. very much; too much 33．—How are you，Bob?一Ted．A．How are you? B．I’m fine．Thank you．C．How do you do? D．Nice to meet you．34．一Hello．I’m Harry Potter．一Hello，my name is Charles Green，but ．A．call my Charles B．call me at CharlesC．call me Charles D．call Charles me35. You ____ buy some reference books when you go to the college.A. couldB. will have toC. must toD. might三、阅读理解 Reading Comprehension（每小题4分，共20分）Passage 1It has been reported that in colleges across the United States, the daytime serial drama known as the soap opera has suddenly become "in". Between the hours of 11 a.m. and 4:30 p.m, college television lounges are filled with soap opera fans who can't wait to see the next episode in the lives of their favorite characters.Actually, soaps are more than a college favorite; they're a youth favorite. When school is out, high-school students are in front of their TV sets. One young working woman admitted that she turned down a higher paying job rather than give up watching her favorite serials. During the 1960's, it was uncommon foryoung people to watch soap operas. The mood of the sixties was very different from now. It was a time of seriousness, and talk was about social issues of great importance.Now, seriousness has been replaced by fun. Young people want to be happy. It may seem strange that they should turn to soap opera, which is known for showing trouble in people's lives. But soap opera is enjoyment. Young people can identify with the soap opera character, who, like the college-age viewer, is looking for happy love, and probably not finding it. And soap opera gives young people a chance to feel close to people without having to bear any responsibility for their problems.1. What is soap opera? ______A. Plays based on science fiction stories.B. Plays based onnon-fiction stories.C. The daytime serial dramas on TV.D. Popular documentary films on TV.2. What can be the best title of the passage? ______A. College student viewers.B. Favorite TV serials.C. Soap opera fans.D. College-age viewers.3. Which is not the reason why the soap opera suddenly becomes "in" according to the passage? _______A. Because the viewers want to be happy and to enjoy themselves.B. Because the soap opera makes young people feel close to their people.C. Because the viewers can find themselves in the soap opera characters.D. Because the young people have to bear the responsibilities for their troubles.4.. What can we learn from the passage? ______A. College students like soap operas more than any other social groups.B. Young people of sixties liked soap operas more than people today.C. Young viewers have turned themselves from the seriousness of sixties to enjoyment now.D. The young as a whole are trying to look for happy love but in vain.5.. What message does the author want to convey to us? _____A. The people's favor toward drama works has been changed for a long time.B. The people's favor toward drama works changes along with the times.C. The people's favor toward drama works is changed by the soap opera.D. The people's favor has changed the drama works.Passage 2How men first learnt to invent words is unknown; in other words, the origin of language is a mystery. All we really known is that men, unlike animals, somehow invented certain sounds to express thought and feelings, actions, and things, so that they could communicate with each other; and that later they agreed upon certain signs, called letters, which could be combined to represent those sounds, and which could be written down. Those sounds, whether spoken or written in letters, we call words.The power of words, then, lies in their associations - the things they bring up before our minds. Words become filled with meaning for us by experience; and the longer we live, the more certain words recall to us the glad and sad events ofour past; and the more we read and learn, the more the number of words that mean something to us increases.Great writers are those who not only have great thoughts but also express these thoughts in words which appeal powerfully to our minds and emotions. This charming and telling use of words is what we call literary style. Above all, the real poet is a master of words. He can convey his meaning in words which sing like music and which by their position and association can move men to tears. We should therefore learn to choose our words carefully and use them accurately, or they will make our speech silly and vulgar . (239words)1. The origin of language is _________A. a legend handed down from the pastB. a matter that is hidden or secret.C. a question difficult to answer.D. a problem not yet solved.2. What is true about words? __________A. They are used t to express feelings only.B. They can not be written downC. They are simply sounds.D. They are mysterious.3. The real power of words lies in their _______.A. propertiesB. characteristicsC. peculiarityD. representative function4.By “association”, the author means __________.A. a special qualityB. a joining of ideas in the mind.C. an appearance which is puzzling.D. a strange feature.5.Which of the following statements about the real poet is NOT true? _________A. He is no more than a master of words.B. He can convey his ideas in words which sing like music.C. He can move men to tears.D. His style is always charming.Passage 3Long, long ago there was a very foolish thief. Do you know what he did one day? When he wanted to steal the bell on his neighbor's door, he walked up to the door, took hold of the bell and pulled hard. The bell made a very loud noise. The thief was afraid and went home.Then he sat down to think, "I must do something about the noise," he said. He thought and thought. At last he had an idea. "Ah, I'll put some cotton in my ears. Then I won't be able to hear the noise." The next day he went to the door of his neighbor, and took hold of the bell. This time he pulled even harder. The bell rang loudly, but the thief did not hear anything. With another hard pull he got the bell out. Just then the neighbor came running out."Steal my bell? I'll teach you a lesson," the angry man shouted. And he hit the thief on the nose.The foolish thief did not know how the neighbor found out he was stealing the bell. "Why did he come out just then?" he wondered.1.The thief was trying to get his neighbor's doorbell.A. TB. F2. The thief put some cotton in his ears so as not to hear anythingA. TB. F3.The neighbor ran out probably because he knew his doorbell was being stolen.A. TB. F4.The neighbor hit the thief to punish him for stealing.A. TB. F5.The thief thought the neighbor couldn't hear the noise of the bell.A. TB.三、完形填空Homesickness is very common among students away from home — even those who had previously been away at overnight camp or traveled far away. There is a difference between being away from home for 8 weeks and being gone for 8 months. There is also a difference between 1 home for a while (knowing you will be going back) and leaving 2 (knowing you may never return). Feeling homesick does not make you less mature or mean you are not ready to be 3 . If you feel homesick, talk to your friends at school about it. 4 they are feeling the same way. 5 family and friends back home, but make sure you 6new relationships at school. If your homesickness does not 7 and does not seem to be getting better after a few months at school, speaking with an adviser might help. Also, remember that going home for the first visit may be difficult8 changes in yourself or your family. Old conflicts do not just disappear once you go to college, and new ones may 9 . Again, if things are too stressful for you 10 handle alone, talk to an adviser.1. A. abandoning B. leaving C. being away D. heading for2. A. forever B. temporarily C. for a short time D. all the time3. A. yourself B. lonely C. of your own D. on your own4. A. Most likely B. It’s impossible C. It’s lucky D. Make sure5. A. Keep in touch with B. Contact with C. Keep contact inD. Communicate6. A. have built B. do C. formed D. develop7. A. go with B. go away C. go over D. go through8. A. thanks to B. because of C. because D. resulting in9. A. appear B. rise C. raise D. grow10. A. too B. so C. to D. not四、完型填空A rich American went into a shop in London. He wanted very much ___1___ a nice-looking watch. He saw a watch and liked it so much thathe decided to buy it. But the owner of the shop asked five hundred dollars for it.While the American was hesitating, a young man suddenly came into the shop, took the watch out of the owner's hand and ran out with it. It all happened in ___2___ seconds. When the owner ran out into the street, the young man had already ___3___ among the people. The American went on. At the next corner, he saw the young man with the stolen watch in his hand, "Do you want to buy a fine watch, sir?" he said in a low voice, "It's only a hundred dollars.""The young man doesn't know I saw him___4___ the watch just now," he thought. The American paid at once and went happily back to his room with the watch. He told his friend about the fine watch. His friend ___5___ a look at the watch and started to shout immediately. He said, "You are a fool. This watch is worth only ten dollars. I'm sure the shop owner and the young man planned all this together."1.A：a few B：disappeared C：to get D：took E：stealing2.A：a few B：disappeared C：to get D：took E：stealing3.A：a few B：disappeared C：to get D：took E：stealing4.A：a few B：disappeared C：to get D：took E：stealing5.A：a few B：disappeared C：to get D：took E：stealingThere were once three sons of a wealthy businessman. 16 they met, the two el-dest, who were twins, 17 to quarrel about which of them should be his father's heir (继承人) . The youngest, who was not 18 ambitious (野心勃勃的), took no part in their argument. As soon as they left home, the father arranged for an adequate income to be provided for 19 of them, but insisted that apart from this they were to be financially self-supporting. The 20 twin, who had the advantage of good looks and a striking personality, decided that he would take up the stage 21 a career. He 22 a small repertory company,acted in minor parts, was always unpunctual (不准时) at rehearsals and was accordingly 23 with his fellow-actors. He earned little and so had to live mainly on his allowance. He occasionally thought of 24 his profession, but always put off 25 a decision, and he became increasingly bored and disillusioned.16. A. whatever B. whenever C. wherever D. however17. A. are used B. used C. using D. are using18. A. at least B. at most C. in the least D. in the most19. A. every B. all C. each D. none20. A. first B. older C. younger D. elder21. A. is B. as C. be D. /22. A. joined B. attended C. went D. joined in23. A. popular B. unpopular C. welcome D. unwelcome24. A. living B. turning C. ending D. changing25. A. making B. make C. decide D. deciding。

《操作系统原理》习题答案一、单项选择题1、（信号量）是一种只能进行P、V操作的特殊变量。

2、一个进程是（PCB结构与程序和数据的组合）。

3、操作系统中，当（时间片完），进程从执行状态转变为就绪状态。

4，设有三个作业J1，J2，J3同时到达，运行时间分别为T1，T2，T3，且T1≤T2 ≤ T3。

若它们在一台处理机上按单道运行，采用短作业优先算法，则平均周转时间为（T1+ 2/3T2 + 1/3T3）。

5、在操作系统中，死锁出现是指（若干进程因竞争资源而无限等待其他进程释放已占有的资源）6.若系统有三个并发进程，都需要同类资源4个，试问该系统不会发生死锁的最少资源数是( 10 ) 。

7、预防死锁的论述中，（可以通过破坏产生死锁的四个必要条件之一或其中几个的方法，来预防发生死锁）条是正确的论述。

8、关于死锁与不安全状态的关系，下列描述正确的有（死锁是一种不安全状态）：9、银行家算法是一种（死锁避免）算法。

10、以下哪种算法不属于多个分区的可变分区存储管理方式的主存分配算法（最后适应分配算法）11、在固定分区管理方式中，处理器执行作业时，对每条指令中的地址要求满足（下限地址≤绝对地址≤上限地址）12、以下叙述中，不正确的是（采用动态和静态重定位的系统都支持“程序浮动”）13、在页式存储管理中，假定地址用m个二进制位表示，其中页内地址部分占用了n个二进制位，那么最大的作业允许有（2(m-n) ）个页面。

14、关于一个分区的存储管理，以下叙述不正确的是（一个分区的存储管理中，必须采用动态重定位的方式进行地址转换）15、下面哪种算法不属于页式虚拟存储管理中的页面调度算法（优先数调度算法）16、缺页中断率与哪个因素无关（作业的逻辑地址）17、很好地解决了“零头”问题的存储管理方法是（页式存储管理）18、在存储管理中，（可变分区管理）可与覆盖技术配合.19、虚拟存储器的最大容量（由计算机的地址结构决定）20、下述（先进先出）页面淘汰算法会产生BELADY现象.21、计算机系统的二级存储包括（主存储器和辅助存储器）22、以下关于主存空间的说法中正确的是（操作系统与硬件的接口信息、操作系统的管理信息和程序等存放在主存储器的系统区）23、联想存储器在计算机系统中是用于（地址变换）24、以下有关可变分区管理中采用的主存分配算法说法中错误的是（最佳适应算法是最好的算法，但后过的较大作业很难得到满足）25、下面关于重定位的有关描述，错误的是（静态重定位中装入主存的作业仍然保持原来的逻辑地址）26、在可变式分区分配方案中，最佳适应算法是将空闲区在空闲区表中按（容量递增）次序排列27、在分页存储系统中，页表是由（操作系统）建立的28、CPU输出数据的速度远远高于打印机的打印速度，为解决这一矛盾，采用（缓冲技术）29、如果I/O设备与存储设备进行数据交换不经过CPU来完成,这种数据交换方式是（DMA方式）30、在下列文件的物理结构中，不利于文件长度动态增长的是（连续结构）31、操作系统有多种类型：允许多个用户以交互方式使用计算机的操作系统，称为（分时操作系统）。

西交《操作系统原理》在线作业
一个进程是（）：
A:由协处理机执行的一个程序
B:一个独立的程序 + 数据集
C:PCB结构与程序和数据的组合
D:一个独立的程序
答案：C
以下叙述中，不正确的是（）
A:采用动态重定位，在必要时可以改变装入的作业在主存中的存放区域B:采用动态重定位的系统支持“程序浮动”
C:采用静态重定位的系统不支持“程序浮动”
D:采用动态和静态重定位的系统都支持“程序浮动”
答案：D
如果分时操作系统的时间片一定，那么( )，则响应时间越长。

A:用户数越少
B:用户数越多
C:内存越少
D:内存越多
答案：B
在固定分区管理方式中，处理器执行作业时，对每条指令中的地址要求满足（）A:下限地址≤绝对地址≥上限地址
B:下限地址≤绝对地址≤上限地址
C:上限地址≤绝对地址≤下限地址
D:上限地址≤绝对地址≥上限地址
答案：B
在多道程序环境下,操作系统以( )作为资源分配的基本单元。

A:作业
B:程序
C:进程
D:线程
答案：C
从总体上说，多道程序设计技术可（）单位时间的算题量。

A:增加
B:减少。

天大15秋季《操作系统原理》在线作业一答案《操作系统原理》在线作业一一、单选题（共20道试题，共100分。

）1.下列进程状态的转换中，哪一个是不正确的（）。

.就绪运行.运行就绪.就绪阻塞.阻塞就绪正确答案：2.一个进程被唤醒意味着（）。

.该进程重新占有了PU.进程状态变为就绪.它的优先权变为最大.其P移至就绪队列的队首正确答案：3.在下列性质中，哪一个不是分时系统的特征。

（）.交互性.同时性.及时性正确答案：4.下列各项步骤中，哪一个不是创建进程所必须的步骤（）。

.建立一个进程控制块P.由PU调度程序为进程调度PU.为进程分配内存等必要的资源.将P链入进程就绪队列正确答案：5.在操作系统中，对信号量S的P原语操作定义中，使进程进入相应阻塞队列等待的条件是（）。

.S>0.S=0.S<0.S10正确答案：6.（）存储管理支持多道程序设计，算法简单，但存储碎片多。

.段式.页式.固定分区正确答案：7.（）不是操作系统关心的主要问题。

.管理计算机裸机.设计、提供用户程序与计算机硬件系统的界面.管理计算机系统资源.高级程序设计语言的编译器正确答案：8.在下列特性中，哪一个不是进程的特性（）。

.异步性.并发性.静态性.动态性正确答案：9.可由PU调用执行的程序所对应的地址空间为（）。

.符号名空间.虚拟地址空间.相对地址空间.物理地址空间10.进程间的基本关系为（）。

.相互独立与相互制约.同步与互斥.并行执行与资源共享.信息传递与信息缓冲正确答案：11.系统出现死锁的原因是（）。

.计算机系统发生了重大故障.有多个封锁的进程同时存在.若干进程因竞争资源而无休止地等待着，不释放已占有的资源.资源数大大少于进程数，或进程同时申请的资源数大大超过资源总数正确答案：12.进程和程序的本质区别是（）。

.存储在内存和外存.顺序和非顺序执行机器指令.分时使用和独占使用计算机资源.动态和静态特征13.两个进程争夺同一个资源（）。

一、选择题1.It was getting _______ , he had to stop to have a rest.A. very darkerB. dark and darkC. darker and darkerD. darkest and darkest2.The film brought the hours back to me A I was taken good care of in that remote village.A. whenB. whereC. thatD. until3.As the busiest woman there, she made _________her duty to look after all the other people's affairs in that town.A. thisB. thatC. oneD. it4.It's high time that he settled down in the country and B a new life.A. startB. startedC. startingD. to st5．I won’t make the ___mistake next time.A. likeB. sameC. nearD. similar6.----She has two best friends.----___of them is in the country.A. AllB. BothC. No oneD. Neither7.This overcoat cost ________. What's more, they are _________small for me.A. very much; veryB. too much; much tooC. much too; too muchD. very much; too much8.— Did the medicine make you feel better?— No. The more ________, ___________ I feel.A. medicine I take; and the worseB. medicine I take; the worseC. I take medicine; the worseD. I take medicine; worse9．一Haven’t seen you for ages!What are you busy doing now?一A．1 hate the weather here．B．My hair is getting a bit longer．C．Yeah，thanks for coming．D．I am working part time in a bookshop，you know．10．—Thanks for your help．—A．My pleasure．B．Never mind．C．Quite right．D．Don’t thank me11.The film brought the hours back to me I was taken good care of in that remote village.A. whenB. whereC. thatD. until12．一Marilyn，I'm afraid I have to be leaving now．—A．That sounds wonderful．B．Oh，so early?C．Not at a11．D．Good luck!13It is not until you have lost your health _________ you know its value.A. untilB. whenC. whatD. that14.It's high time that he settled down in the country and B a new life.A. startB. startedC. startingD. to start 15．一Paul，?一Oh，that’s my father! And beside him，my mother．A．what is the person over thereB．who’s talking over thereC．what are they doingD．which is that16．一Hi，Tom，how’s everything with you?— ，and how are you?A．Don’t mention it B．Hmm, not too badC．Thanks D．Pretty fast17.----The baby is hungry.----But there’s ___milk in the bottle.A. littleB. a littleC. fewD. a few18.Would you like something _________?A. drinkB. to drinkC. drinkingD. for drinking19.The wild flowers looked like a soft orange blanket _________ the desert.A. coveringB. coveredC. coverD. to cover20. _______ is the population of Paris?A. How manyB. How muchC. HowD. What21.----___is your girl friend like?----She is very kind and good-lookingA. HowB. WhatC. WhichD. Who 22．一That’s a beautiful dress you have on!—A．Oh，thanks．I got it yesterday．B．Sorry，it’s too cheap．C．You can have it．D．See you later．23.It is not until you have lost your health ___________ you know its value.A. untilB. whenC. whatD. that24.As the busiest woman there, she made _________her duty to look after all the other people's affairs in that town.A. thisB. thatC. oneD. it25.It was getting ________ , he had to stop to have a rest.A. very darkerB. dark and darkC. darker and darkerD. darkest and darkest26.— Did the medicine make you feel better?— No. The more ________, ___________ I feel.A. medicine I take; and the worseB. medicine I take; the worseC. I take medicine; the worseD. I take medicine; worseart27．一Why didn’t you come to my birthday party yesterday?一A．Excuse me，my friend sent me a flower．B．Fine，I never go to birthday parties．C．Ha…ha，I don’t like birthday parties．D．Sorry，but my wife had a car accident28．一Hi，welcome back!Had a nice trip?一A．Oh，fantastic!Fresh air，and sunshine every day．B．Come on．I’ve got lots of fun．C．By the way，I don’t like Saturdays．D．Well，I'll look forward to your phone call．29.The wild flowers looked like a soft orange blanket ________ the desert.A. coveringB. coveredC. coverD. to cover30. ________ is the population of Paris?A. How manyB. How muchC. HowD. What31.Would you like something ________?A. drinkB. to drinkC. drinkingD. for drinking32.This overcoat cost _______. What's more, they are ________small for me.A. very much; veryB. too much; much tooC. much too; too muchD. very much; too much33．—How are you，Bob?一Ted．A．How are you? B．I’m fine．Thank you．C．How do you do? D．Nice to meet you．34．一Hello．I’m Harry Potter．一Hello，my name is Charles Green，but ．A．call my Charles B．call me at CharlesC．call me Charles D．call Charles me35. You ____ buy some reference books when you go to the college.A. couldB. will have toC. must toD. might三、阅读理解 Reading Comprehension（每小题4分，共20分）Passage 1It has been reported that in colleges across the United States, the daytime serial drama known as the soap opera has suddenly become "in". Between the hours of 11 a.m. and 4:30 p.m, college television lounges are filled with soap opera fans who can't wait to see the next episode in the lives of their favorite characters.Actually, soaps are more than a college favorite; they're a youth favorite. When school is out, high-school students are in front of their TV sets. One young working woman admitted that she turned down a higher paying job rather than give up watching her favorite serials. During the 1960's, it was uncommon for young people to watch soap operas. The mood of the sixties was very different from now. It was a time of seriousness, and talk was about social issues of great importance.Now, seriousness has been replaced by fun. Young people want to be happy. It may seem strange that they should turn to soap opera, which is known for showing troublein people's lives. But soap opera is enjoyment. Young people can identify with the soap opera character, who, like the college-age viewer, is looking for happy love, and probably not finding it. And soap opera gives young people a chance to feel close to people without having to bear any responsibility for their problems.1. What is soap opera? ______A. Plays based on science fiction stories.B. Plays based on non-fiction stories.C. The daytime serial dramas on TV.D. Popular documentary films on TV.2. What can be the best title of the passage? ______A. College student viewers.B. Favorite TV serials.C. Soap opera fans.D. College-age viewers.3. Which is not the reason why the soap opera suddenly becomes "in" according to the passage? _______A. Because the viewers want to be happy and to enjoy themselves.B. Because the soap opera makes young people feel close to their people.C. Because the viewers can find themselves in the soap opera characters.D. Because the young people have to bear the responsibilities for their troubles.4.. What can we learn from the passage? ______A. College students like soap operas more than any other social groups.B. Young people of sixties liked soap operas more than people today.C. Young viewers have turned themselves from the seriousness of sixties to enjoyment now.D. The young as a whole are trying to look for happy love but in vain.5.. What message does the author want to convey to us? _____A. The people's favor toward drama works has been changed for a long time.B. The people's favor toward drama works changes along with the times.C. The people's favor toward drama works is changed by the soap opera.D. The people's favor has changed the drama works.Passage 2How men first learnt to invent words is unknown; in other words, the origin of language is a mystery. All we really known is that men, unlike animals, somehow invented certain sounds to express thought and feelings, actions, and things, so that they could communicate with each other; and that later they agreed upon certain signs, called letters, which could be combined to represent those sounds, and which could be written down. Those sounds, whether spoken or written in letters, we call words.The power of words, then, lies in their associations - the things they bring up before our minds. Words become filled with meaning for us by experience; and the longer we live, the more certain words recall to us the glad and sad events of our past; and the more we read and learn, the more the number of words that mean something to us increases.Great writers are those who not only have great thoughts but also express these thoughts in words which appeal powerfully to our minds and emotions. This charming and telling use of words is what we call literary style. Above all, the real poet is a master of words. He can convey his meaning in words which sing like music andwhich by their position and association can move men to tears. We should therefore learn to choose our words carefully and use them accurately, or they will make our speech silly and vulgar . (239words)1. The origin of language is _________A. a legend handed down from the pastB. a matter that is hidden or secret.C. a question difficult to answer.D. a problem not yet solved.2. What is true about words? __________A. They are used t to express feelings only.B. They can not be written downC. They are simply sounds.D. They are mysterious.3. The real power of words lies in their _______.A. propertiesB. characteristicsC. peculiarityD. representative function4.By “association”, the author means __________.A. a special qualityB. a joining of ideas in the mind.C. an appearance which is puzzling.D. a strange feature.5.Which of the following statements about the real poet is NOT true? _________A. He is no more than a master of words.B. He can convey his ideas in words which sing like music.C. He can move men to tears.D. His style is always charming.Passage 3Long, long ago there was a very foolish thief. Do you know what he did one day? When he wanted to steal the bell on his neighbor's door, he walked up to the door, took hold of the bell and pulled hard. The bell made a very loud noise. The thief was afraid and went home.Then he sat down to think, "I must do something about the noise," he said. He thought and thought. At last he had an idea. "Ah, I'll put some cotton in my ears. Then I won't be able to hear the noise." The next day he went to the door of his neighbor, and took hold of the bell. This time he pulled even harder. The bell rang loudly, but the thief did not hear anything. With another hard pull he got the bell out. Just then the neighbor came running out."Steal my bell? I'll teach you a lesson," the angry man shouted. And he hit the thief on the nose.The foolish thief did not know how the neighbor found out he was stealing the bell. "Why did he come out just then?" he wondered.1.The thief was trying to get his neighbor's doorbell.A. TB. F2. The thief put some cotton in his ears so as not to hear anythingA. TB. F3.The neighbor ran out probably because he knew his doorbell was being stolen.A. TB. F4.The neighbor hit the thief to punish him for stealing.A. TB. F5.The thief thought the neighbor couldn't hear the noise of the bell.A. TB.三、完形填空Homesickness is very common among students away from home — even those who had previously been away at overnight camp or traveled far away. There is a difference between being away from home for 8 weeks and being gone for 8 months. There is also a difference between 1 home for a while (knowing you will be going back) and leaving 2 (knowing you may never return). Feeling homesick does not make you less mature or mean you are not ready to be 3 . If you feel homesick, talk to your friends at school about it. 4 they are feeling the same way. 5family and friends back home, but make sure you 6 new relationships at school. If your homesickness does not 7 and does not seem to be getting better after a few months at school, speaking with an adviser might help. Also, remember that going home for the first visit may be difficult 8 changes in yourself or your family. Old conflicts do not just disappear once you go to college, and new ones may 9 . Again, if things are too stressful for you 10 handle alone, talk to an adviser.1. A. abandoning B. leaving C. being away D. heading for2. A. forever B. temporarily C. for a short time D. all the time3. A. yourself B. lonely C. of your own D. on your own4. A. Most likely B. It’s impossible C. It’s lucky D. Make sure5. A. Keep in touch with B. Contact with C. Keep contact inD. Communicate6. A. have built B. do C. formed D. develop7. A. go with B. go away C. go over D. go through8. A. thanks to B. because of C. because D. resulting in9. A. appear B. rise C. raise D. grow10. A. too B. so C. to D. not四、完型填空A rich American went into a shop in London. He wanted very much ___1___ a nice-looking watch. He saw a watch and liked it so much that he decided to buy it. But the owner of the shop asked five hundred dollars for it.While the American was hesitating, a young man suddenly came into the shop, took the watch out of the owner's hand and ran out with it. It all happened in___2___ seconds. When the owner ran out into the street, the young man had already ___3___ among the people. The American went on. At the next corner, he saw the young man with the stolen watch in his hand, "Do you want to buy a fine watch, sir?" he said in a low voice, "It's only a hundred dollars.""The young man doesn't know I saw him ___4___ the watch just now," he thought. TheAmerican paid at once and went happily back to his room with the watch. He told his friend about the fine watch. His friend ___5___ a look at the watch and started to shout immediately. He said, "You are a fool. This watch is worth only ten dollars. I'm sure the shop owner and the young man planned all this together."1.A：a few B：disappeared C：to get D：took E：stealing2.A：a few B：disappeared C：to get D：took E：stealing3.A：a few B：disappeared C：to get D：took E：stealing4.A：a few B：disappeared C：to get D：took E：stealing5.A：a few B：disappeared C：to get D：took E：stealingThere were once three sons of a wealthy businessman. 16 they met, the two eldest, who were twins, 17 to quarrel about which of them should be his father's heir (继承人) . The youngest, who was not 18 ambitious (野心勃勃的), took no part in their argument. As soon as they left home, the father arranged for an adequate income to be provided for 19 of them, but insisted that apart from this they were to be financially self-supporting. The 20 twin, who had the advantage of good looks and a striking personality, decided that he would take up the stage 21 a career. He 22 a small repertory company, acted in minor parts, was always unpunctual (不准时) at rehearsals and was accordingly 23 with his fellow-actors. He earned little and so had to live mainly on his allowance. He occasionally thought of 24 his profession, but always put off 25 a decision, and he became increasingly bored and disillusioned.16.A.whatever B.whenever C.wherever D.however17.A.are used ed ing D.are using18.A.at least B.at most C.in the least D.in the most19.A.every B.all C.each D.none20.A.first B.older C.younger D.elder21.A.is B.as C.be D./22.A.joined B.attended C.went D.joined in23.A.popular B.unpopular C.welcome D.unwelcome24.A.living B.turning C.ending D.changing25.A.making B.make C.decide D.deciding。

西交《操作系统原理（高起专）》在线作业
从总体上说，多道程序设计技术可（）单位时间的算题量。

A.增加
B.减少
C.维持
正确答案:A
有一类操作系统的系统响应时间的重要性超过系统资源的利用率，它被广泛地应用于卫星控制、导弹发射、飞机飞行控制、飞机订票业务等领域是（）。

A.分时操作系统
B.实时操作系统
C.批处理系统
D.网络操作系统
正确答案:B
在操作系统中进程是一个具有一定独立功能程序在某个数据集合上的一次（）。

A.并发活动
B.运行活动
C.单独操作
D.关联操作
正确答案:B
文件系统的主要目的是（）。

A.实现对文件的按名存取
B.实现虚拟存贮器
C.提高外围设备的输入输出速度
D.用于存贮系统文档
正确答案:A
操作系统中，进程与程序的重要区别之一是（）。

A.程序有状态而进程没有
B.进程有状态而程序没有
C.程序可占有资源而进程不可
D.进程能占有资源而程序不能
正确答案:B。

15春西交《操作系统原理》在线作业答案1.在操作系统中，进程是一个动态的概念，而程序是一个静态的概念。

2.在请求调页系统中，选择最先进入内存的页面予以淘汰的算法称为FIFO算法。

3.允许多用户将若干个作业提交给计算机系统集中处理的操作系统称为批处理操作系统。

4.实现CPU和外部设备并行工作的硬件支持是通道和中断。

5.在虚拟存储器系统中常使用联想存储器进行管理，它是按内容寻址的。

6.顺序文件是文件的逻辑结构中既适合于交互方式应用，也适合于批处理方式应用的组织方式。

7.在请求分页管理中，若采用先进先出（FIFO）页面置换算法，可能会产生“Belady异常”，“Belady异常”指的是分配的页面数增加，缺页中断的次数也可能增加。

8.先进先出页面置换算法（FIFO）会产生Belady异常现象。

9.对索引文件进行检索时，应先从FCB中读出文件索引表始址。

10.通道是一种设备控制器。

1.在操作系统中，进程是一个动态的概念，与之相对的，程序是一个静态的概念。

2.请求调页系统中，选择最先进入内存的页面予以淘汰的算法被称为FIFO算法。

3.允许多用户将若干个作业提交给计算机系统集中处理的操作系统被称为批处理操作系统。

4.通道和中断是实现CPU和外部设备并行工作的硬件支持。

5.联想存储器常被用于虚拟存储器系统中进行管理，它是按内容寻址的。

6.顺序文件是一种既适合于交互方式应用，也适合于批处理方式应用的文件逻辑结构组织方式。

7.在请求分页管理中，若采用先进先出（FIFO）页面置换算法，可能会产生“Belady异常”，即分配的页面数增加，缺页中断的次数也可能增加。

8.先进先出页面置换算法（FIFO）会产生Belady异常现象。

9.对索引文件进行检索时，应先从FCB中读出文件索引表始址。

10.通道是一种设备控制器。

11.实时操作系统在卫星控制、发射、飞机飞行控制、飞机订票业务等领域有广泛应用，因为它们更注重系统响应时间而不是系统资源的利用率。

西交《计算机网络原理》在线作业
试卷总分:100 得分:100
一、单选题 (共 30 道试题,共 60 分)
1.篡改是破坏了数据的（）
A.完整性
B.一致性
C.保密性
D.可利用性
答案:A
2.下列属于广域网拓扑结构的是( )。

A.树形结构
B.集中式结构
C.总线形结构
D.环形结构
答案:B
3.E-mail地址格式正确的表示是（）。

A.主机地址@用户名
B.用户名，用户密码
C.电子邮箱号，用户密码
D.用户名@主机域名
答案:D
4.内部网关协议RIP是一种广泛使用的基于()的协议。

A.链路状态算法
B.距离矢量算法
C.集中式路由算法
D.固定路由算法
答案:B
5.避免“拒绝授权访问或拒绝服务”是为保障网络信息或数据的( )。

A.完整性
B.可用性
C.保密性
D.可靠性
答案:B
6.网络协议主要要素为()。

A.数据格式、编码、信号电平
B.数据格式、控制信息、速度匹配
C.语法、语义、同步
D.编码、控制信息、同步
答案:C。