单项选择题
A.1~2 B.2~3 C.1 D.4~6
A.100~200mmB.200~300mmC.300mm以下D.50~100mm
A.用除盐水浸泡 B.用除盐水冲洗 C.用饱和食盐水浸泡 D.用10%的食盐水浸泡