9. "Can you tell me about a time you've clashed with a supervisor?"
Don't take the bait on this one. It's not an opportunity for you to unload on your idiot manager and convince your potentially soon-to-be new manager how right you are. This is a test, so make sure you pass.
Your interviewer wants to see how you handle disagreements with higher-ups. So please don't call your former boss a huge a-hole and talk about how much of an idiot he was. It doesn't matter one bit whether or not you were right, what they're looking for is whether or not you were able to work things out, move forward, and stay productive. So whatever story you tell here, make sure it has a happy ending. Even if you have to admit you were wrong, that's not such a bad thing because it shows an ability to take responsibility and, better yet, learn from it.