A-A+
When are airplanes not fuel efficient？A．On sho
问题详情
When are airplanes not fuel efficient？
A．On short trips.
B．On long trips.
C．When flying over cities.
D．When flying at high altitudes.
参考答案
正确答案：A
解析：短文提到，飞机在短途旅行时并不是 fuel efficient，故A为正确答案。
考点：
