A.40~50B.50~70C.70~100D.80~100
A.結(jié)構(gòu)復(fù)雜B.流速較高C.結(jié)構(gòu)復(fù)雜,流速較低D.結(jié)構(gòu)復(fù)雜,流速較高
A.流程長(zhǎng)B.壓力損失小C.流程短,壓力損失較大D.流程長(zhǎng),壓力損失較大