Hi all,
Wow! Thanks for all your inputs. It is very much appreciated. I asked this question because it was a question which I was asked during an interview recently, and without going into too much detail, I just told them the basics, which I myself do not know if it was the correct answer. In fact, I cant even really remember what I told the interviewers, except that it was due to a higher TAS and also the air being less dense.
Once again, I really appreciate the comments and in depth explanations. I guess I'll know what to tell the interviewers the next time round.
Cheers,
DECU