A:铁屑被磁化成小磁针
B:每一条磁感线从S极指向N极
C:条形磁铁中央附近磁场最强
D:磁感线可以相交
一个化学方程式能得到很多信息,你从反应2H2+O22H2O能得到哪些信息?请任写两点.
(1)____ ;(2)____ .
His methods are regarded as the of working by his leaders and workmates.
下列划线字中声母完全相同的一项是( )。