1 - Your hand is SO GOOD, that you could slow play and try to get the most money out of it. By calling, if the flush don't hit, he may fire again. You could min-raise or raise but, you WANT a call. He doesn't have a 6 ot 7 that could hurt you.

2 - Same thing... You are very strong, you say that he is not very likely to have AQ or AJ, that could beat you with a str8 because he raises all the time. So slow-play it again.

You don't get good hands like this all the time so you must extract much more money out of them.

3 - Hard one... I would raise to 5 or 6 k, not only double the BB of the chip leader. On the flop... scary, bet 1/2 or 2/3 of the pot seems fine. God fold after the A hits.

Congratulations