Backcourt or no call?

[NC_rec_ref]

2nd year ref-want to get it right. Situation last night:
Sit 1. Team A with ball in backcourt, A1 moves ball to front court in her possession. Closely guarded by B1 and B1 knocks ball away from A1, off A1 leg and into backcourt. A1 returns to backcourt and regains possession. I made no call, coach went bananas. Is it backcourt or no call?

Sit. 2 Same situation, only this time A1 dribbles it off her shoe, ball goes into backcourt and she retrieves. Backcourt?

Sit. 3 (sorry, I think in 3's-drives my company crazy!)
Same situation only now, B1 knocks ball directly into backcourt. A1 retrieves. BAckcourt?

Want to get this right before I call again this Sat. All wisdom welcomed.
Thanks,
CH