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單項(xiàng)選擇題

Any friction fit, tightness or adhesion of the part of any load being lifted should be broken by wedge or tapping and not by increasing the load on the applianceAccording to this sentence, ()

A.the lifting appliance can always lift the freight within its rated load
B.attention should be paid in order not to break the wedge when lifting cargo
C.sometimes the lifting work needs other assistance other than the lifting appliance
D.lifting work should be done with every part fit, tightness or adhesion

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