One disadvantage of alliances foreseen by the critics is that air travel may be moreexpensive as a result of
A. less convenience.
B. higher operation costs.
C. less competition.
D. more joint marketing.
上颌第一磨牙远中接触区位于
A. 颌1/3处
B. 颌1/3水平的颊1/3与1/3交界处
C. 颌1/3水平的中1/3处
D. 颌缘中1/3处
E. 颌1/3水平的中1/3与舌1/3交界处
条件宏的条件项是一个
A. 字段列表
B. 算术表达式
C. 逻辑表达式
D. SQL语句
According to the passage, which of the following categories of travellers will gainmost from airline alliances
A. Travellers who fly frequently economy class.
B. Travellers who fly frequently business class.
C. Travellers who fly occasionally during holidays.
D. Travellers who fly economy class once.in a while.
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