On chess ethics

It's the last round of a tournament and Alice and Bob are paired up. Which of these scenarios are morally acceptable to you?

1. Alice advances if she wins, Bob is already out of contention. Bob throws the game.
2. Alice and Bob both advance if they draw. They play out the Berlin draw.
3. Alice and Bob both advance if they draw. Alice is rated 400 Elo higher than Bob. They play out the Berlin draw.