问题 问答题


阅读以下路由器配置的技术说明,根据要求回答问题1~问题5。
【说明】
某局域网通过两个路由器划分为3个子网,其网络拓扑结构和IP地址分配如图6-8所示.

【问题1】
以下是路由器R1的配置命令列表,请将(1)~(3)空缺处的命令/参数填写完整,以实现路由器 R1的正确配置。
Router>en
Router>conf term
Router (config) #hostname R1
(1)
R1 (config-if) #ip address 192.168.1.2 255.255.255.0
R1 (config-if) #no shutdown
R1 (config-if) #int s0
R1 (config-if) #ipa ddress (2)
R1 (coafig-if) #no shutdown
R1 (config-if) #clock rate 56000
R1 (config-if) #exit
R1 (config) #ip routing
R1 (config) #ip route 0.0.0.0 0.0.0.0 (3)
R1 (config) #ip classless
R1 (config) #exit
R1#copy run start

答案

参考答案:

解析:(1) R1 (config) #int e0 (2) 192.168.2.1 255.255.255.0 (3) 192.168.2.2(1)空缺处前面的命令是在全局配置模式(Router (config) #),而后一个命令是在路由器R1接口 e0 (192.168.1.2/24)的子配置模式(R1 (config-if) #),根据前后两个命令的提示可知,此处应该是一条进入接口e0子配置模式的命令(R1 (config) #interface e0)。 (2)空缺处前面的命令(R1 (config-if) #int s0)的作用是进入路由器R1接口s0的子配置模式,(2)空缺处所在行的“ip address”进一步提示该处填写的是s0接口的IP地址信息。根据图6-8拓扑结构中的Ⅲ地址信息可知,s0接口的IP地址是192.168.2.1,子网掩码是255.255.255.0。 (3)空缺处前面的命令ip routing的作用是允许配置路由。(3)空缺处所在行的“ip route”提示该行用于完成某条静态路由的配置。目标地址设置为0.0.0.0 0.0.0.0表示默认路由,根据图6-8的拓扑结构,(3)空缺处应填入路由的下一跳地址192.168.2.2。

阅读理解

(2013·高考新课标全国卷Ⅰ,B)The baby is just one day old and has not yet left hospital.She is quiet but alert (警觉).Twenty centimeters from her face researchers have placed a white card with two black spots on it.She stares at it carefully.A researcher removes the card and replaces it by another,this time with the spots differently spaced.As the cards change from one to the other,her gaze(凝视) starts to lose its focus—until a third,with three black spots,is presented.Her gaze returns:she looks at it for twice as long as she did at the previous card.Can she tell that the number two is different from three,just 24 hours after coming into the world?

Or do newborns simply prefer more to fewer? The same experiment,but with three spots shown before two,shows the same return of interest when the number of spots changes.Perhaps it is just the newness? When slightly older babies were shown cards with pictures of objects (a comb,a key,an orange and so on),changing the number of objects had an effect separate from changing the objects themselves.Could it be the pattern that two things make,as opposed to three? No again.Babies paid more attention to squares moving randomly on a screen when their number changed from two to three,or three to two.The effect even crosses between senses.Babies who were repeatedly shown two spots became more excited when they then heard three drumbeats than when they heard just two;likewise (同样地) when the researchers started with drumbeats and moved to spots.

小题1:The experiment described in Paragraph 1 is related to the baby’s________.

A.sense of hearing

B.sense of sight

C.sense of touch

D.sense of smell小题2:Babies are sensitive to the change in________.

A.the size of cards

B.the colour of pictures

C.the shape of patterns

D.the number of objects小题3:Why did the researchers test the babies with drumbeats?

A.To reduce the difficulty of the experiment.

B.To see how babies recognize sounds.

C.To carry their experiment further.

D.To keep the babies’ interest.小题4:Where does this text probably come from?

A.Science fiction.

B.Children’s literature.

C.An advertisement.

D.A science report.

填空题