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單項選擇題

A spreader bar is used to（）.

A.increase the lifting capacity
B.increase the lifting radius
C.protect the slings
D.protect the upper part of a load

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單項選擇題

A strong back refers to a（）.

A.bar securing a cargo port
B.centerline vertical bulkhead
C.deep beam
D.spanner stay

單項選擇題

A tank which is not completely full or empty is called（）.

A.pressed
B.slack
C.inertial
D.elemental