What does the father mean?
A:He wants his daughter to stay at home.
B:He will offer any help to his daughter.
C:He will give the talk for his daughter.
如果y<0<x,则化简xx+xyxy的结果为( )
下列有关实验的描述中,错误的是( )
中国第八次公民科学素质调查结果显示,2010年,具备基本科学素质的公民仅占3.27%,和发达国家比,有较大差距。以下是公民科学素质调查问卷中的四个判断正误题,其中错误的是( )