Bar raiser was by far the most difficult all around, because there is no way to really prepare and the question asked after the small talk about the position and your prior experience, seems completely irrelevant to the position. And as nerves are already high, it is frustrating because of course you want to give an answer that will get you hired, but at the sane time it's hard if you don't understand what they are asking for. An example is like estimate how many trees there are in Washington state, or tell me the best way to get home from these two routes. And of course you can't ask for more information and if you try to add information you may be told it's irrelevant. I would suggest really relaxing and try to understand what they are really trying to gain from asking such strange off topic questions.
