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问题 选择题
点P（-1，2）到直线8x-6y+15=0的距离为（　　）
A．2B．
1
2
C．1D．
7
2
答案

点P（-1，2）到直线8x-6y+15=0的距离：

d=

|-8-12+15|
64+36
=
1
2
，

故选B．

计算题
竖式计算。
（1）10.65×6.6=（2）7.91×2.08=
（3）0.23×0.25=（4）0.12×5.05=
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单项选择题 A1型题

One of the main advantages of a graphite-furnace atomizer is that（）

A.It requires only very small quantities of a sample

B.It requires metal.ions in aqueous solution

C.It does not produce background emission like a flame

D.It does not get hot like a flame
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