设等比数列{an}的各项都为正数,若a3=1,a3=9,则公比q=() A.3 B.2 C.-2 D.-3
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A.numberB.amountC.manyD.much
A. number B. amount C. many D. much
甲坛有8个小球,乙坛有4个小球,所有小球颜色各不相同,现从甲坛中取2个小球,乙坛中取1个小球,则取出3个球的不同取法共有() A.224种 B.112种 C.32种 D.1320种
A.whereB.whichC.thatD.how
A. where B. which C. that D. how
A.altogetherB.talkC.alwaysD.also
A. altogether B. talk C. always D. also