The tone of the author at the end is
A. regretful.
B. optimistic.
C. dissatisfied.
D. pessimistic.
查看答案
According to the passage, todays celebrities are those who
A. are notable thanks to the publicity of the media.
B. are distinguished by enduring contributions.
C. have big name for what they had achieved.
D. are well-known because of the company image they present.
55是一个直接广播地址，可以同时将数据报广播至本网络内。()
IP地址指定的不是一台计算机，而是计算机到一个网络的连接。()
TCP/IP协议从底层到顶层分为：网络接口层、互连层、传输层和()等4个层次。
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