下列储存药品的方法中,正确的是( )
A.浓硫酸保存在橡胶塞试剂瓶中
B.浓硝酸保存在无色试剂瓶中
C.金属钠保存在煤油中
D.氢氧化钠溶液保存在玻璃塞试剂瓶中
答案:C
—What were you doing when you heard Malaysian airlines flight lost?
—I my homework.
A.were doing.
B.am doing.
C.was doing.
D.is doing.
在教学过程中,如何贯彻实施因材施教原则?