A.ab段:DN50mm,通气立管(T):DN100mm,ef段:DN150mm,坡度:i=0.015 B.ab段:DN75mm,通气立管(T):DN100mm,ef段:DN150mm,坡度:i=0.020 C.ab段:DN75mm,通气立管(T):DN75mm,ef段:DN150mm,坡度:i=0.020 D.ab段:DN75mm,通气立管(T):DN100mm,ef段:DN150mm,坡度:i=0.015正确答案B
A.ab段:DN50mm,通气立管(T):DN100mm,ef段:DN150mm,坡度:i=0.015 B.ab段:DN75mm,通气立管(T):DN100mm,ef段:DN150mm,坡度:i=0.020 C.ab段:DN75mm,通气立管(T):DN75mm,ef段:DN150mm,坡度:i=0.020 D.ab段:DN75mm,通气立管(T):DN100mm,ef段:DN150mm,坡度:i=0.015正确答案B