On a crane, the boom indicator tells the operator what angle the boom angle is compared to

What is meant by the term“luffing the boom”of a crane ________．

A.Stopping the boom

B.Topping or lowering the boom

C.Moving the boom left or right

D.All of the above

The boom indicator on a crane will indicate the ______．

A.Length of the boom

B.Angle of the boom

C.Lifting capacity of the boom

D.Direction of the boom

The boom stops are installed on an offshore crane to ______.

A.prevent the boom from being raised too high

B.prevent the boom from swinging

C.support the boom when not in use

D.prevent the boom from being lowered

For any given pedestal crane，when the boom is lengthened，the lifting capacity is ______．

A.unchanged

B.increased

C.eliminated

D.decreased

The boom stops on a pedestal crane prevent the boom from ______.

A.being raised too high

B.swinging at sea

C.overloading when not in use

D.being lowered too low

How should you signal the crane operator to lower the boom？______.

A.With arm extended and fingers closed, point thumb downward

B.With arm extended downwards and forefinger pointing down, move hand in small horizontal circles

C.Extend arm with the palm down, and hold this position rigidly

D.With hands clasped in front of your body

A.raise the boom

B.raise the hook

C.raise the boom and hook

D.check the boom stop

How should you signal the crane operator to lower the boom and raise the load ________．

A.Extend arm and point finger in the direction to move the boom

B.Extend arm with thumb pointing downward and flex fingers in and out

C.With forearm vertical and forefinger pointing up，move hand in small horizontal circles

D.With arm extended downwards and forefinger pointing down，move hand in small horizontal circles

What does “evel-luffing” accomplish during crane operations ________．

A.It prevents the load from swinging when the boom level is adjusted

B.Less power is needed when topping the boom with a load on the hook

C.It maintains the height of the load above the deck

D.All of the above

________ is used for heaving up and slacking away the anchor and chain

A.A winch

B.A windlass

C.A crane

D.A jumbo boom