A.1.5℃~2℃ B.0.5℃~1℃ C.1.2℃~1.5℃
A.關(guān)閉水封閥 B.關(guān)閉截止閥 C.關(guān)閉V型水封管 D.堵盲板
A.50℃ B.70℃~90℃ C.100℃