SDCAR2010【逻辑入门】（八）Assumptions

athenawujj

23. On a certain day, nine scheduled flights on Swift Airlines were canceled. Ordinarily, a cancellation is due to mechanical problems with the airplane scheduled for a certain flight. However, since it is unlikely that Swift would have the mechanical problems with more than one or two scheduled flights on a single day(Premise), some of the nine cancellations were probably due to something else. (Conclusion)
The argument depends on which one of the following assumptions?（Necessary Assumption）
Ordinarily mechanical problems just for few flight→Swift airlines canceled nine flight, there is another reason.
A.    More than one or two airplanes were scheduled for the nine canceled flights.
B.    Swift Airlines has fewer mechanical problems than do other airlines of the same size.
C.    Each of the canceled flights would have been longer than the average flight on Swift Airlines.
D.    Swift Airlines had never before canceled more than one or two scheduled flights on a single day.
E.    All of the airplanes scheduled for the canceled flights are based at the same airport.

Dear SDCQR;i don't understand why choose A?

athenawujj

SDCAR，Hello,I got stuck.
When i do the CR,i cannot do it quickly.I don't know what  i should do to improve the speed.
Here is my plan.CAN YOU GIVE ME SOME IDEAS?
1.After reading your series, I redo OG.
2.Because i have the test next month, i want to go straight to the GWD?
is it ok??