0n cargo booms,preventers are（）.

1、A cargo boom is a（）.

A cargo boom is a（）.Adouble sized mattress consists of more than 890 coilsBspar extending from a mast or a king postCflap（Becker rudder）can...

2、The boom stops are installed on an off

The boom stops are installed on an offshore crane to（）.Aprevent the boom from being raised too highBprevent the boom from swingingCsupport the boom when not in useDprevent the boom from being lowered

3、Dry cargoes are those commodities that

Dry cargoes are those commodities that（）.Anever leak but may be spoiled by leakageBsometimes leak and damage themselvesCoften leak and damage other cargoDneither leak nor will be damaged by leakage

4、0n a crane ,the boom indicator tells t

0n a crane ,the boom indicator tells the operator what angle the boom angle is compared to the（）.Avertical positionBhorizontal positionCboom stop angleDminimum radius angle

5、On cargo booms，preventers are（）.

On cargo booms，preventers are（）.Aauxiliary guysBextra fair leadsCsteel bandsDsto

6、When a cargo boom or crane is rated at

When a cargo boom or crane is rated at varying capacities，there will be a table at the controls which relates safe working load to（）.Awinch speedBboom strengthCload radiusDcable strength