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單項選擇題

In the cargo winch, spur reduction gearing transfers the motor drive to （）.

A.the toping light
B.the board brake
C.the fail-safe
D.the barrel shaft

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單項選擇題

For occasional heavy loads, two cranes can be arranged to work together. The operating （） for deck crane motors may be hydraulic electric.

A.principle
B.medium
C.instruction
D.voltage

單項選擇題

In a general cargo crane, three principal movements are （）；（）；（）.

A.hoisting；luffing；slewing
B.lifting；raising；lowering
C.rotating；raising；handling
D.hosting；lowering；moving