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單項選擇題

Stress on the topping lift of a swinging boom can be reduced by（）.

A.rigging a back stay
B.raising the boom
C.increasing the mechanical advantage of the cargo purchase
D.taking all slack out of the preventer

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單項選擇題

Sometimes the contract（）that the lump sum freight must be paid in advance and will not be returnable even if the vessel and／or her cargo are lost.

A.provide
B.provides
C.providing
D.be provided

單項選擇題

Securing cargo by running timbers from an upper support down to the cargo，either vertically or at an angle，is called（）.

A.braces
B.dunnage
C.shores
D.toms

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