该图例在采暖施工图表示()。
A.方形补偿器
B.止回阀
C.角阀
D.蝶阀
参考答案:A
During a fire drill on a ship,what action is required?()
A.Start each fire pump
B.Launch and run a lifeboat
C.Inventory rescue and fire equipment
D.Inspect fire hoses
以下三种燃料中发热值最高的是()。
A.高炉煤气
B.焦炉煤气
C.天然气