A:在无色的溶液中:K+、Na+、MnO4﹣、SO42﹣
B:在pH=11的溶液中:CO32﹣、Na+、NO3﹣、SO42﹣
C:水电离出的c(H+)=10﹣12mol•L‾1的溶液中:Cl﹣、HCO3﹣、NO3﹣、NH4+
D:在酸性溶液中:Na+、NH4+、SO42﹣、S2O32﹣
— Do you often watch the show If You Are the One?
— Yes. It is ______ a successful programme that it attracts _______ many audiences.
He held a glass with care because he was afraid of ____ (break) it.
如图,AB是⊙O的直径,点D在AB的延长线上,点C在⊙O上,CA=CD,∠CDA=30°.试判断直线CD与⊙O的位置关系,并说明理由.