20 ways to say "I don't know."

As opposed to the pleasure felt by telling someone that "they're wrong", there's always a little sting in answering a question about your project or your science by saying "I don't know." Here's a few ways of saying those 3 unpleasant words:

1. [single shoulder shrug]
2. Let me check on that.
3. That's a really good question.
4. So this is really preliminary data, but we felt that it was important that we get this out there first...
5. Hmmmmmmmmmmmmmm.................
6. Look at the time! Gotta go!
7. [hands outstretched, palms up]
8. Here's the NMR, Professor Sames!
9. [Eyes narrowed] Did (insert hated rival's name) put you up to this?
10. I think that's in my lab notebook.
11. I haven't looked at that yet.
12. The literature doesn't really speak to that.
13. But, it's obviously the thermodynamic product!
14. [double shoulder shrug]
15. You know, that's something we're going to look at in our next round of experiments.
16. [silence] Any other questions?
17. IDK my BFF Jill?
18. Huh.
19. You know, there are some questions that we haven't been able to answer.
20. I don't know.*

*(Only to be used in dire circumstances or if you have a sudden attack of extreme honesty.)