Quite right JJ330. I suspect they will expect measured answers so suggesting RR is more expensive than GE, Hm? Was RR not the pioneer of the large bypass. Remember RB211 and L1011. It caused them to go to the wall.
In relation to the cars, same as for the a/c: GE has XYZ pounds of thrust in whatever model: RR has 'enough'.
However; I think I'd stick with 2 v 3 shafts. The interviewer may not have a sense of humour.