Edison had more than 1,000 inventions his lifetime. [ ]
A. among
B. at
C. during
D. on
答案:C
治疗支原体肺炎的首选抗生素为
A.青霉素
B.SMZ-CO
C.丁胺卡那
D.红霉素
E.阿莫西林
为了除去密闭容器内空气中的氧气,得到较纯净的氮气,用于燃烧的物质最好是选用( )
A.木炭
B.硫粉
C.红磷
D.蜡烛