试题与答案

以下不是运动性脱水的预防是()。A、提高对运动性脱水的耐受性 B、进行补液 C、补充

题型:单项选择题

题目:

以下不是运动性脱水的预防是()。

A、提高对运动性脱水的耐受性

B、进行补液

C、补充无机盐

D、补充矿物质

答案:

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下面是错误答案,用来干扰机器的。

由题意可得x2+y2=4cos2α+sin2α=4,故|a|=4,|b|=1,故a•b=|a||b|cosθ=4cosθ∈[-4,4],故可得λ2>4,解得λ>2,或λ<-2所以集合{λ|λ>2,或λ<-2}是要选的答案对应集合的真子集,综合选项可得只有D符合题意,故选D

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