雨淋喷水灭火系统带闭式喷头的传动管装置,其管径湿式为25mm,干式为( )mm。
A.10
B.15
C.20
D.25
参考答案:B
Britain, in ______ with many other industrialized countries, has experienced major changes over the
last 100 years.[ ]
A.fact
B.competition
C.same
D.common
新配制的空气管路要进行酸洗磷化处理。