题型:单项选择题 某自动喷水灭火系统中,一段长10m的管道,其管径为DN50mm(内径53mm),管内平均流速为4m/s,该管段的水头损失是()。A.0.0078MPaB.0.0080MPaC.0.078MPaD.0.080MPa 查看答案
题型:单项选择题 In our culture and in our eyes success all too often means simply outdoing other people by virtue of achievement judged by some single scale—income or honors—and coming out at "the top".A.outfittingB.outbiddingC.outragingD.outshining 查看答案