按规定，备用照明的照度不应低于正常照明的( )。
A．5%
B．10%
C．15%
D．20%
参考答案：B
It is clear that ______little money he earns can hardly support _____ family as large as his.[ ]
A. the; a
B. a; the
C. /; a
D. /; the
可用于胃镜消毒的是（）
A.75%乙醇
B.2%过氧乙酸
C.0.5%碘伏
D.10mg/L二溴海因
E.2%戊二醛
