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问题 选择题

将1、、、按右侧方式排列．若规定（m，n）表示第m排从左向右第n个数，则（4，2）与（21，2）表示的两数之积是（ ▲ )．

A．1

B．2

C．2

D．6

答案

答案：D

（4，2）表示第4排从左向右第2个数是：，

（21，2）表示第21排从左向右第2个数，可以看出奇数排最中间的一个数都是1，

第21排是奇数排，最中间的也就是这排的第1个数是1，那么第2个就是：，

• =6,故选D

阅读理解

The moon looks bigger than the stars at night. But in fact, it is smaller than any other stars. The moon looks big to us, because it is closer to us than any stars. The moon goes around the earth. It makes one trip about four weeks. The moon is a round ball and looks beautiful.

Now people know quite a lot about the moon. There is no air or water on the moon, so there are not any trees or animals, or people on it. The moon gets its light(光) from the sun, but some places on the moon are quite dark. It’s very hot on the moon during the day, but it’s very cold at night.

小题1:          looks bigger than the stars at night.

A．Moon

B．Star

C．Earth

D．Sun小题2:There is            on the moon.

A．no anything

B．nothing

C．no hills or rivers

D．no air or water小题3:The sun             to the moon.

A．gets light

B．gives light

C．gives air

D．gets air小题4:The moon gets its light from         .

A．the sun

B．the star

C．air

D．the earth
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单项选择题

为了提高软件产品的质量和可靠性，对某些无法避开的差错，使其影响减至最小程度所采用的技术是（）

A.容错技术

B.避开错误技术

C.检测技术

D.排错技术
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