The exhaust boilers are used to recove

1、Safety valves on a boiler vent to the

Safety valves on a boiler vent to the （）.Afuel tankBbilgeCatmosphereDauxiliary exhaust line

2、Logbooks are used to record the events

Logbooks are used to record the events occurring when（）.Athe ship is in a harborBthe ship is at anchorageCthe ship is underwayDall of the above

3、（） are used to limit the pressure in a

（） are used to limit the pressure in any particular portion and mainly control the pressure after the valve.ARelief valvesBCheck valvesCSafety valvesDReducing valve

4、（）are used to digest the sewage to pro

（）are used to digest the sewage to produce innocuous sludge in a biological sewage treatment plant.Aanaerobic bacteriaBaerobic bacteriaCair bubblesDdisinfection chemical

5、The boiler feed water check valves are

The boiler feed water check valves are located on the （）Afeed pump suction lineBhot wellCshell of the feed heaterDfeed lines to the boiler

6、The quadrantal spheres are used to（）.

The quadrantal spheres are used to（）.Aremove deviation on the intercardinal headingsBremove deviation on the cardinal compass headingsCremove heeling errorDcompensate for induced magnetism in vertical soft iro