题目内容:
根据下列选项,回答题。Currently,different types of 1 0perations involving different combinations are taking place.Sea/air combines in itself the 2 of sea transport and the 3 0f air transport.The economics of this combination mode favors 4 value items such as electronics,electrical goods,computers,and photographic equipment.In air/road.road transport is now being increasingly used for 5 air freight over long distances,sometimes across national boundaries,to connect with the main bases of airlines operating long haul services such as transpacific,transatlantic and inter—continental.
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