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單項選擇題

What is meant by the term“l(fā)uffing 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

你可能感興趣的試題

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

單項選擇題

They（）loading at 1400 hours．

A.started
B.finished
C.completed
D.reported