单项选择题
Safety valves on a boiler vent to the （）.
A.fuel tank B.bilge C.atmosphere D.auxiliary exhaust line
单项选择题 The boiler feed pump discharge pressure is higher than the steam drum pressure to （）.
单项选择题 If in doubt as to the true water level when a boiler is being oil-fired, you should （）.
单项选择题 The boiler feed water check valves are located on the （）
