A.CABB.ABCC.BCAD.ACB
A.30:2B.15:1C.15:2D.30:15
A.右心房或上下腔靜脈胸腔段的壓力B.左心房與上腔靜脈的壓力C.右心房或下腔靜脈的壓力D.左心房與下腔靜脈的壓力