Thank you very much for your reply, Bandit, John and Jas.
I read your reply carefully and can I have this conclusion?
For the angle of climb, we have to consider the tail wind and head wind as they will affect the GS. Tail wind increase GS while headwind decrease GS, so that the horizontal distance covered by aircraft A & B is different, making their angle of climb different, given that they are having the same rate of climb.
For the rate of climb, we have to consider IAS only. Tail wind and head wind is meaningless when talking about rate of climb. I know that IAS is a good indication of lift available. Regardless the wind direction, as long as both aircraft have the same IAS, they will have the same performance (e.g., same rate of climb).
Can I have this conclusion? Thank you very much!!!
re Bandit: No I can't see anything looks like Heisenberg uncertainty principle in the BAK textbook.
re Jas: I think I know more after reading your explanation!
re John: Your last sentence helped me to connect things together.