A.9% B.15% C.18% D.26% E.30%
A.19~21cm B.22~24cm C.26~28cm D.30~32cm E.35cm以上
A.與氣管中軸延長線夾角呈25°~30° B.長2~3cm C.經(jīng)氣管墜入的異物,左、右主支氣管機(jī)會(huì)相等 D.其前上方有上腔靜脈 E.右主支氣管管徑較左側(cè)者粗,支氣管鏡易插入