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问题 选择题

下列有关内环境的叙述中，正确的是[ ]

A．动物的细胞外液是内环境

B．动物体内所有的液体是内环境

C．内环境的理化因素绝对稳定

D．内环境稳态仅由神经调节维持

答案

答案：A

填空题
若a，b，c是△ABC三边，则
(a-b-c)2
+|b-c-a|+
(c-a-b)2
=______．
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听力题

小题1:I want to travel, e______________to English-speaking countries.

小题2:Keeping p__________, such as dogs and cats is more and more popular among young and old.

小题3:Have you ever h_______________ of the interesting story?

小题4:Would you m_______________ turning down the music?

小题5:He has been c________________ stamps for five years.
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