A.3~5℃ B.6~8℃ C.10~12℃ D.13~15℃
A.30s B.40s C.50s B.60s
A.油泵的吸人壓力 B.油泵的排出壓力和吸人壓力之差 C.冷水泵的排出壓力 D.冷水泵的排出壓力和吸入壓力之差