What can be concluded about "modem" ?A.It converts data from one form. to another.B.It will be out of date soon.C.It serves as a link between senders and recipients of message.D.It transmits message more efficiently than other devices.

题目

What can be concluded about "modem" ?

A.It converts data from one form. to another.

B.It will be out of date soon.

C.It serves as a link between senders and recipients of message.

D.It transmits message more efficiently than other devices.


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更多“What can be concluded about "modem" ?A.It converts data from one form. to another.B.It will be out of date soon.C.It serves as a link between senders and recipients of message.D.It transmits message more efficiently than other devices.”相关问题
  • 第1题:

    One can never find out what the other people think about from his facial expression.

    A、It means "wearing the mask"

    B、It means "keeping ideas to herself"

    C、It means "telling everyone her bright ideas"

    D、It means "agreeing with others’ ideas"


    参考答案:A

  • 第2题:

    Digital data can also be represented by (71)signals by use ofa modem. The modem converts a series of binary voltage (72) into an analog signal by encoding the digital data ontoa carrier frequency. The resulting signal occupies a certam spectrum of (73) centered about the carTier and may be propagated acrossa medium suitable for that carrier. The most common modems represent digital data in the voice(74)and hence allow those datato be propagated over ordinary voice-grade (75 )lines At the other end of the line, another modem demodulates the signal to recover the original data

    (71)

    A.analog

    B.digital

    C.Modem

    D.electric


    正确答案:A
    数字数据也可以通过调制解调器用模拟信号来表示。调制解调器把数字数据编码为一种载波频率,从而可以把二进制电压序列转换为模拟信号。产生的信号占用了以某一频率为中心的载波频带,可以通过适合于该载波的介质进行传播。大多数通用的调制解调器表示话音频带的数字数据,因而允许这些数据在通常的话音级电话线路上传播。在线路的另一端,另外一个调制解调器对信号进行解调并恢复原来的数据。

  • 第3题:

    What can be concluded from the passage?

    A. A fuelling ambition plays a leading role in one’s success.

    B. A responsible adviser is more important than the knowledge of writing.

    C. As to the growth of a genius, I.Q. doesn’t matter, but just his/her efforts.

    D. What really matters is what you do rather than who you are.


    正确答案:D

  • 第4题:


    What can be inferred from paragraph 1 about theatrical dance in the late nineteenth century?( )

    A.It influenced many artists outside of the field of dance.
    B.It was very similar to theatrical dance of the early nineteenth century.
    C.It was more a form of entertainment than a form of serious art.
    D.It was a relatively new art form in the United States.

    答案:C
    解析:
    推断题。根据题干关键词theatrical dance定位到文章第一段的第一句。该句意为“洛伊·富勒发现十九世纪末的剧场舞蹈在艺术上并没有什么成就”。第二句话中,她认为自己是一位艺术家,而不仅仅是一位娱乐性的演艺人员。A项“影响了许多舞蹈领域之外的艺术家”,偷换了原文主语,且“舞蹈领域之外”与原文不符。B项“与十九世纪初的戏剧舞蹈非常相似”,原文未做比较。D项“这在美国是一种相对较新的艺术形式”,原文未提及。因此C项“更像是一种娱乐形式而不是严肃的艺术形式”为正确推断。

  • 第5题:

    HSRP has been configured between two Company devices.  What kind of message does an HSRP  configured router send out every 3 seconds?()

    • A、 Retire
    • B、 Coup
    • C、 Resign
    • D、 Send
    • E、 Hello

    正确答案:E

  • 第6题:

    In which case would you use a FULL OUTER JOIN?()

    • A、Both tables have NULL values.
    • B、You want all unmatched data from one table.
    • C、You want all matched data from both tables.
    • D、You want all unmatched data from both tables.
    • E、One of the tables has more data than the other.
    • F、You want all matched and unmatched data from only one table.

    正确答案:D

  • 第7题:

    Which two statements about subqueries are true?()

    • A、A single row subquery can retrieve data from only one table.
    • B、A SQL query statement cannot display data from table B that is referred to in its subquery, unless table B is included in the main query's FROM clause.
    • C、A SQL query statement can display data from table B that is referred to in its subquery, without including table B in its own FROM clause.
    • D、A single row subquery can retrieve data from more than one table.
    • E、A single row subquery cannot be used in a condition where the LIKE operator is used for comparison.
    • F、A multiple-row subquery cannot be used in a condition where the LIKE operator is used for comparison.

    正确答案:B,D

  • 第8题:

    单选题
    We can learn from the Kimberly case that _____.
    A

    children are more than just personal possessions of their parents

    B

    the biological link between parent and child should be emphasized

    C

    foster homes bring children more pain and suffering than care

    D

    biological parents shouldn’t claim custody fights after their child is adopted


    正确答案: A
    解析:
    主旨归纳题。通过金伯利一案,法官按孩子的心愿,从有利于孩子的出发点,把孩子判给其养父监护、抚养,可看出这种判决体现了文章结尾的评论:孩子不是父母可以操纵的私有财产,我们应该从有利于孩子心愿出发而不能只从所谓生理上的亲情出发,反映了司法的公正,故A项“孩子不单单是父母的私有财产”与此同义。

  • 第9题:

    单选题
    What can NOT be concluded from the passage?
    A

    More and more young people are volunteering to carry out suicide bombings since the conflict according to militant groups’ data.

    B

    Israel’s intensified blockade has brought Gaza a darker sky.

    C

    All the Palestinian militant groups are united against Israel.

    D

    Young Palestinian men are feeling depressed but sense a hopeful future.


    正确答案: C
    解析:
    题目问的是:下列哪一项是不能从文章中得到的?文章第9段提到“But the powerful Israeli gunfire and internal divisions, most due to fight between Hamas and Fatah, make most tries in vain.”,意思是说“以色列强大的炮火和内部分歧,主要由于哈马斯和法塔赫之间的战争,使得大部分努力付之东流。”并没有提到所有巴勒斯坦武装组织联合起来对抗以色列,其他三项都有原文与之对应。故选C。

  • 第10题:

    多选题
    Which three statements about subqueries are true? ()
    A

    A main query can have more than one subquery.

    B

    A subquery can have more than one main query.

    C

    The subquery and main query must retrieve data from the same table.

    D

    The subquery and main query can retrieve data from different tables.

    E

    Only one column or expression can be compared between the subquery and main query.

    F

    Multiple columns or expression can be compared between the subquery and main query.


    正确答案: C,D
    解析: 暂无解析

  • 第11题:

    单选题
    What is the difference between a CSU/DSU and a modem?()
    A

    A CSU/DSU converts analog signals from a router to a leased line; a modem converts analog signals from a router to a leased line.

    B

    A CSU/DSU converts analog signals from a router to a phone line; a modem converts digital signals from a router to a leased line.

    C

    A CSU/DSU converts digital signals from a router to a phone line; a modem converts analog signals from a router to a phone line.

    D

    A CSU/DSU converts digital signals from a router to a leased line; a modem converts digital signals from a router to a phone line.


    正确答案: B
    解析: 暂无解析

  • 第12题:

    单选题
    It may be concluded from this passage that _____.
    A

    Islamic artists have had to create architectural decoration with images of flowers or geometric forms

    B

    history teachers are more objective than artists

    C

    it is more difficult to study art history than general history

    D

    people and stories from the Bible were painted on churches and other Buildings in order to popularize the Bible


    正确答案: C
    解析:
    B、C、D在文中均未提及或暗示,故可排除。文章末段最后两句讲,中东艺术的主要特点之一是缺乏人和动物图像,这反映了伊斯兰教认为雕像是邪恶的信仰。由此我们可以得出结论,伊斯兰教的艺术家必须创造花、几何图案的建筑装饰。

  • 第13题:

    Networks can be interconnected by different devices. In the physical layer, networks can be connected by(66)or hubs, which just move the bits from one network to an identical network. One layer up we find bridges and switches, which operate at data link layer. They can accept(67), examine the MAC address, and forward the frames to a different network while doing minor protocol translation in the process. In the network layer, we have routers that can connect two networks. If two networks have(68)network layer, the router may be able to translate between the packet formats. In the transport layer we fmd transport gateway, which can interface between two transport connections. Finally, in the application layer, application gateways translate message(69). As an example, gateways between Internet e-mail and X.400 e-mail must(70)the e-mail message and change various header fields.

    A.repeaters

    B.relays

    C.connectors

    D.modems


    正确答案:A
    解析:网络可以用不同的设备互连。在物理层,用中继器或集线器互连,这些设备只是在相同的网络之间传关比特串。在上面的数据链路层,可以使用网桥或交换机,这些设备接收数据帧,检查MAC地址,并可以实现少量的协议转换,把数据帧转发到不同的网络中。在网络层,我们使用路由器连接两个网络。如果两个网络的网络层不同,路由器能够对分组格式进行转换。在传输层,我们使用传输网关,它可以在两个传输连接之间建立接口。最后,在应用层,应用网关实现消息语法之间的翻译。例如,在Internet邮件和X.400邮件之间的网关可以对邮件报文进行语法分析,对报文的各个报头字段做出改变。

  • 第14题:

    What is the difference between a CSU/DSU and a modem?()

    A. A CSU/DSU converts analog signals from a router to a leased line; a modem converts analog signals from a router to a leased line.

    B. A CSU/DSU converts analog signals from a router to a phone line; a modem converts digital signals from a router to a leased line.

    C. A CSU/DSU converts digital signals from a router to a phone line; a modem converts analog signals from a router to a phone line.

    D. A CSU/DSU converts digital signals from a router to a leased line; a modem converts digital signals from a router to a phone line.


    参考答案:D

  • 第15题:

    (71)is the science of hiding information。Whereas the goal of cryptography is to make data unreadable by a third party。the goal of steganography is to hide the data from a third party。In this article,I will discuss what steganography is,what purposes it serves,and will provide an example using available software。

      There are a large number of steganographic(2)that most of us are familiar with(especially if you watch a lot of spy movies),ranging from invisible ink and microdots to secreting a hidden message in the second letter of each word of a large body of text and spread spectrum radio communication。With computers and networks,there are many other ways of hiding informations,such as:

      Covert channels(c,g,Loki and some distributed denial-of-service tools use the Internet Control(3)Protocol,or ICMP,as the communication channel between the“bad guy”and a compromicyed system)

      Hidden text within Web pages

      Hiding files in“plain sight”(c,g,what better place to“hide”a file than with an important sounding name in the c:\winnt system32 directory)

      Null ciphers(c,g,using the first letter of each word to form a hidden message in an otherwise innocuous text)

      steganography today,however,is significantly more(4)than the example about suggest,allowing a user to hide large amounts of information within image and audio。These forms of steganography often are used in conjunction with cryptography so the information is double protected;first it is encrypted and then hidden so that an advertisement first。find the information(an often difficult task in and of itself)and the decrypted it。

      The simplest approach to hiding data within an image file is called(5)signature insertion。In this method ,we can take the binary representation of the hidden data and the bit of each byte within the covert image。If we are using 24-bit color the amount and will be minimum and indiscriminate to the human eye。

    (73)处的单词应是

    A.Member
    B.Management
    C.Message
    D.Mail

    答案:C
    解析:
    译文如下:
    信息隐藏学是隐藏信息的科学。而密码学的目的是让数据对于第三方不可识别,而信息隐藏学的目的则是将数据对于第三方隐藏起来。本文,我将论述信息隐藏学是什么、它的目的是什么,并且会提供使用可行软件的案例。
    有许多信息隐藏的方法实际上我们都很熟悉(特别是如果你看过一些谍战片!),从隐型墨水和微小的点点,到将信息暗含在一大段文字的每个单词的第二个字母中,还有无线通信中的扩频技术等等。使用计算机和网络,有许多其他的隐藏信息的方法,比如:
    转换信道(e.g.,洛基和一些分布式拒绝服务工具使用网际控制管理协议,或叫做icmp,作为“坏人”和受攻击的系统之间的通信信道)
    隐藏信息在网页中
    隐藏文件在“眼皮儿底下”(比如,隐藏信息在什么地方比给它取一个重要的熟悉名字放置在目录C:\winnt\system32中更好?)
    空域算法(比如,使用一段毫不相干的文字中每个单词的首写字母来表示一个隐藏的信息)
    隐写术在今天,然而明显比上面的例子更强大,允许用户隐藏大量的信息在图像和音频文件,这些形式的隐写术通常用于结合密码学,信息是双重保护的。
    最简单的方法来隐藏数据,是将信息嵌入在图像文件的像素位上(lsb),在这种方法中,我们可以把隐藏的二进制表示数据和覆盖的每个字节的图片,如果我们使用的是24位颜色,数量的变化是最小的并且肉眼是看不见的。

  • 第16题:

    What is the difference between a CSU/DSU and a modem?()

    • A、A CSU/DSU converts analog signals from a router to a leased line; a modem converts analog signals from a router to a leased line
    • B、A CSU/DSU converts analog signals from a router to a phone line; a modem converts digital signals from a router to a leased line
    • C、A CSU/DSU converts digital signals from a router to a phone line; a modem converts analog signals from a router to a phone line
    • D、A CSU/DSU converts digital signals from a router to a leased line; a modem converts digital signals from a router to a phone line

    正确答案:D

  • 第17题:

    You are subneting in the network, out of network address,what’s feature can add one more address?


    正确答案:ip subnet-zero.

  • 第18题:

    Which three statements about subqueries are true? ()

    • A、A main query can have more than one subquery.
    • B、A subquery can have more than one main query.
    • C、The subquery and main query must retrieve data from the same table.
    • D、The subquery and main query can retrieve data from different tables.
    • E、Only one column or expression can be compared between the subquery and main query.
    • F、Multiple columns or expression can be compared between the subquery and main query.

    正确答案:A,C,E

  • 第19题:

    Which two statements are true about simple views?()

    • A、Views can be created as read only.
    • B、Views are data segments like tables.
    • C、Views can be created on the basis of more than one table.
    • D、Data manipulation language (DML) operations cannot be performed on views.

    正确答案:A,C

  • 第20题:

    单选题
    In which case would you use a FULL OUTER JOIN?()
    A

    Both tables have NULL values.

    B

    You want all unmatched data from one table.

    C

    You want all matched data from both tables.

    D

    You want all unmatched data from both tables.

    E

    One of the tables has more data than the other.

    F

    You want all matched and unmatched data from only one table.


    正确答案: D
    解析: 暂无解析

  • 第21题:

    单选题
    HSRP has been configured between two Company devices.  What kind of message does an HSRP  configured router send out every 3 seconds?()
    A

     Retire

    B

     Coup

    C

     Resign

    D

     Send

    E

     Hello


    正确答案: C
    解析: 暂无解析

  • 第22题:

    多选题
    Which two statements about subqueries are true? ()
    A

    A single row subquery can retrieve data from only one table.

    B

    A SQL query statement cannot display data from table B that is referred to in its subquery, unless table B is included in the main query's FROM clause.

    C

    A SQL query statement can display data from table B that is referred to in its subquery, without including B in its own FROM clause.

    D

    A single row subquery can retrieve data from more than one table.

    E

    A single row subquery cannot be used in a condition where the LIKE operator is used for comparison.

    F

    A multiple-row subquery cannot be used in an INSERT statement to insert multiple rows at a time.


    正确答案: A,F
    解析: 暂无解析

  • 第23题:

    单选题
    What is the difference between a CSU/DSU and a modem?()
    A

    A CSU/DSU converts analog signals from a router to a leased line; a modem converts analog signals from a router to a leased line

    B

    A CSU/DSU converts analog signals from a router to a phone line; a modem converts digital signals from a router to a leased line

    C

    A CSU/DSU converts digital signals from a router to a phone line; a modem converts analog signals from a router to a phone line

    D

    A CSU/DSU converts digital signals from a router to a leased line; a modem converts digital signals from a router to a phone line


    正确答案: A
    解析: 暂无解析