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單項選擇題

Administrations should bear in mind the significance of （） in maintaining safety of life and property at sea and in preventing marine pollution.

A.advanced nautical equipment
B.advanced performance main engines
C.emergency equipment
D.communication and language skills

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單項選擇題

Adjust （） by means of lead wire.

A.the clearance of the main bearing
B.the diameter of main bearing
C.the gap of main beating
D.the tolerance of main bearing

單項選擇題

Additives （） protective layers on metal surfaces guarding them against corrosion.

A.damage
B.form
C.dissolve
D.contaminate

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