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问题 单项选择题 A1/A2型题

聚光镜的位置可以升降，用以调节（）

A.分辨率

B.放大倍数

C.光线的强弱

D.折射率

E.光线方向

答案

参考答案：C

解析：聚光镜可以通过位于载物台下方的聚光镜调节旋钮进行上下调节，调节光线的强弱。

单项选择题

Currently the Pentium chip or (71) , made by (72) , is the most common CPU though there are many other companies that produce processors for personal computers. One example is the CPU made by Motorola which is used in Apple computers. With faster processors the clock speed becomes more important. Compared to some of the first computers which operated at below 30 megahertz ( (73) ) the Pentium chips began at 75 megahertz in the late 1990g. As of mid 2003 speeds now exceed 3000 + megahertz or 3 gigahertz (check your local computer store for the latest speed) . It depends on the (74) that the chip is housed in, or the (75) , as to whether you are able to upgrade to a faster chip. The motherboard contains the circuitry and connections that allow the various component to communicate with each other.

A. MHz B. MEG C. MTZ D. MGH
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判断题

课外活动是课堂教学的延伸。（ ）
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