A:xming@sina.com.cn
B:xming
C:pop3.sina.com.cn
D:smtp.sina.com.cn
词语释义选出与句子中划线部分意义最接近的选项。—Today, many young people look up to those famous basketball players. —Yes.They are heroes in the eyes of young people.
如图,以(1,﹣4)为顶点的二次函数y=ax2+bx+c的图象与x轴负半轴交于A点,则一元二次方程ax2+bx+c=0的正数解的范围是( )
研究性学习小组测定实验室里一瓶久置的NaOH固体是否变质.
【提出问题】NaOH固体是否变质?
【猜想与假设】猜想1:没变质,全部是NaOH;
猜想2:全变质,全部是Na2CO3
猜想3:部分变质,既含有NaOH,又含有Na2CO3;