How much is the percent of air transportation in all modes? （） Less than 1%。 Lowest。 Lower。 Low。
what kind of products do the air carriers deliver? （） The high value。 Low density or weight。 A and B。 Shortest time to transport。
What is the disadvantage for air transportation? （） Quick but not safe。 Less frequency。 It can’t lift heavy goods。 The highest cost in all transport modes。
What is the meaning of trend?（） General direction。 Developing road。 Way。 Path。
What is the same meaning as “Internationalization”?（） Nationalization。 Globalization。 Integration。 Standardization。
The international trade needs the （） to fulfill its transaction.
