单机操作系统可以定义为这样一个系统软件，它管理着一台计算机的主要操作，分别是( ) Ⅰ．进程 Ⅱ．内存分配 Ⅲ．文件输入输出 Ⅳ．设备输入输出 Ⅴ．存储管理 Ⅵ．处理机调度 Ⅶ．安全管理
A. Ⅰ、Ⅱ、Ⅲ、Ⅳ
B. Ⅱ、Ⅲ、Ⅳ、Ⅴ
C. Ⅲ、Ⅳ、Ⅴ、Ⅵ
D. Ⅳ、Ⅴ、Ⅵ、Ⅶ
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如果网络的传输速率为56Kb/s，要传输5Mb的数据大约需要的时间是( )。
A. 10分钟
B. 13分针
C. 1小时10分钟
D. 30分钟
The author thinks that the invention of the computer is a revolution in that______.
A. the computer has revolutionized the workings of the human mind
B. the computer can do the tasks that could only be done by people before
C. it has helped to switch to an information technology
D. it has a great potential impact on society
一幅使用了颜料1和颜料4的原稿可能被创作的最早时间是：
A. 公元1000年
B. 公元1050年
C. 公元1100年
D. 公元1150年
One of the effects of directed research is to______.
A. give rise to feelings of hostility among scientists of different branches
B. involve an increasing number of scientists in a lot of extra work
C. get scientists directly involved in research projects with immediate industrial applications
D. yield fewer results with a greater amount of manpower and materials
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