已知a=log20.3,b=20.1,c=0.21.3,则a,b,c的大小关系是[ ]
A.a<b<c
B.c<a<b
C.a<c<d
D.b<c<a
答案:C
—— ___________ do you have this kind of match? —— Once a year.
A.How long
B.How often
C.How many
D.How much
主要与肺癌相关的是()
A.石棉纤维
B.滑石粉
C.EB病毒
D.单纯疱疹病毒
E.雌激素