题目

在(),2,,,,,中,正数的个数为( )A. 1个 B. 2个 C. 3个 D. 4个 答案:【答案】B【解析】根据幂的运算,绝对值的定义来化解图中式子,根据正数的定义得到答案.(-3)=-3,故不是正数,2,是正数,-(-3)2=-9,故不是正数,-32=-9,故不是正数,-|-3|=-3,故不是正数,|-3|=3,是正数,a2,若a=0,则不是正数,故答案选B. He started early so that he ________ there in time. [  ] A. could get B. got C. had got D. would have got
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