单项选择题
A.length of the boom B.angle of the boom C.lifting capacity of the boom D.direction of the boom
Stop（）the derrick at once，the gooseneck is bent.A.to us...
单项选择题Stop（）the derrick at once，the gooseneck is bent.
A.to use B.to operate C.maneuvering D.using
On no account（）to be exceeded.A.is the S.W.L. of the cr...
单项选择题On no account（）to be exceeded.
A.is the S.W.L. of the crane B.are the S.W.L. of the crane C.the S.W.L. of the crane is D.the S.W.L.of the crane are
On a ship crane，the load chart relates the allowable lo...
单项选择题On a ship crane，the load chart relates the allowable load to the combination of boom length and（）.
A.boom angle B.boom strength C.load radius D.cable strength
