A.5 B.10 C.15 D.20
A.氣密測(cè)試 B.檢查燃?xì)庥镁?br /> C.打開(kāi)門(mén)窗使空氣流通 D.切斷水電及燃?xì)夤?yīng)
A.60% B.70% C.80% D.90%