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问题 选择题

在低倍镜下口腔上皮细胞的物像和高倍镜下同一细胞的物像相比较，前者的情况是[ ]

A．物像较小，视野较暗

B．物像较小，视野较亮

C．物像较大，视野较暗

D．物像较大，视野较亮

答案

答案：B

单项选择题

在VLAN的划分中，不能按照下列( )方式定义其成员。

A．交换机端口

B．MAC地址

C．操作系统类型

D．IP地址
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单项选择题

Personal computers are used by one person at a time. The largest personal computer, or PC.S, can fit on a (1) . Some of these (2) have more than one microprocessor. (3) the primary processor, which is a general-purpose device, a PC may have one or more processors to (4) special kinds of work. Some machines, (5) , have maths processors, others have graphics processors to help process photographs and other illustrations. Still others have (6) processors.

Office workers also use PCS that are not (7) to a network. These machines are used for (8) tasks as word processing, performing financial calculations, and organizing and (9) bodies of information called databases. People use PCS at (10) for some of the same kinds of tasks. They use word processing programs for (11) communication, financial software for household budgets. Individuals also use their home computers to play (12) and to communicate (13) the internet.

Small, portable PCS are (14) with people who often work away from their desks. The (15) include laptop computers, which can be (16) on the lap; notebook computers, which are about the (17) of a loose leaf notebook; and palmtop, or handheld computers, which can be operated while (18) in the hand. Laptop and notebook computers have the same (19) as desktop computers. Palmtop computers have less power but still (20) some advanced capabilities. For example, they can process household financial data.

18（）

A.held 

B.holding 

C.took 

D.taking
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