There _____ some water in the glass. [ ]
A. are
B. is
C. am
答案:B
能对抗肾上腺素收缩血管的药物是
A.阿托品
B.普萘洛尔
C.多巴胺
D.酚苄明
E.新斯的明
3()
A.data flow diagram
B.entity relationship model
C.requirements model
D.object model