A:c(H+)=c(OH-)=10-6mol/L溶液
B:pH=7的溶液
C:使石蕊试液呈紫色的溶液
D:酸与碱恰好完全反应生成正盐的溶液
— What did he _______ just now?— Sorry, I didn't catch his words. I_______ about something else.
试在图中画出钟表两指针像的位置.
三角形具有____性,平行四边形不具备____。