题目内容
10Base--5工作站到收发器的距离范围是 (42) 。最多使用 (43) 各中继器连接干线段。 10 Base-2 一个干线上最多支持 (44) 个工作站，它使用 (45) 来连接网络接口卡和电缆相连。细缆以太网10Base-2 连接点不需要使用 (46) 部件。10Base-T工作站连接至一个中心集线器或集中器，其作用相当一个 (47) ，它的拓扑结构是 (48) ，MAC层使用 (49) 协议。在以太网中，5类非屏蔽双绞线可以适用于物理层的 (50) 。 （42）处填（）。
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阅读以下说明，回答问题1～3。[说明] 有关系R，有依赖关系 AE→B AC→D CE→B CFE→BA FE→4A A→C [问题1] 求出关系模式的候选码。
There is a comparison between change in the MP3 industry and that in a different sector.
Karl Von Linne (or Linnaeus, as he is widely known) was a Swedish biologist who devised the system of Latinised scientific names for living things that biologists use to this day. When he came to (1)_____ people into his system, he put them into a group called Homo—and Linne's hairless fellow humans are still known biologically as Homo sapiens. (2)_____ the group originally had a second member, Homo troglodytes. It lived in Africa, and the pictures show it to be covered (3)_____ hair. Modern (4)_____ are not as generous as Linne in welcoming other species into Man's lofty (5)_____, and the chimpanzee is now referred to (6)_____ Pan troglodytes. But Pan or Homo, there is no (7)_____ that chimps are humans' nearest living relatives, and that if the secrets of what makes humanity special are ever to be (8)_____, understanding why chimps are not people, nor people chimps, is a crucial part of the process. That, in turn, means looking at the DNA of the two species, (9)_____ it is here that the (10)_____ must originate. One half of the puzzle has been (11)_____ for several years: the human genome was published in 2001. The second has now been added, with the announcement in this week's Nature (12)_____ the chimpanzee genome has been sequenced as well. For those expecting (13)_____ answers to age-old questions (14)_____, the publication of the chimp genome may be something of an (15)_____. There are no immediately obvious genes-present in one, but not the other-that account for such characteristic human (16)_____ as intelligence or even hairlessness. And (17)_____ there is a gene connected with language, known as FOXP2, it had already been discovered. But although the preliminary comparison of the two genomes (18)_____ by the members of the Chimpanzee Sequencing and Analysis Consortium, the multinational team that generated the sequence, did not (19)_____, any obvious nuggets of genetic gold, it does at least show where to look for (20)_____. Read the following text. Choose the best word (s) for each numbered blank and mark A, B, C or D on ANSWER SHEET 1.16（）
共享硬件、软件和数据资源为目标的计算机系统，称为计算机网络。在一个使用循环调度的系统中，s表示执行进程切换所需要的时间，q表示循环的时间片，r表示进程在发生I/O阻塞前平均运行时间。(a)如果q=∞，CPU 效率是 (31) ；(b)如果q＞r，那么，CPU的效率是 (32) ；(c) s＜q＜r，CPU的效率是 (33) ；(d)s=q＜r，效率为 (34) ；(e) q几乎为零时，CPU的效率是 (35) 。 （35）处填（）。
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