I may be able to help with a select few but some just bring up more questions:
Do pilots take crash-courses?
Unfortunately, they're most always part of them.
Why do people without a watch look at their wrist when you ask them what time it is?
They're looking for their hand perchance they have any time on it.
If most car accidents occur within five miles of home, why doesn't everyone just move 10 miles away?
The majority go with the fad; also, if you're going to have an accident, why be surrounded by strangers?
If man evolved from monkeys and apes, why do we still have monkeys and apes?
Perhaps due to another scientific deduction: things tend to revert to their original state.
I went to a bookstore and asked the saleswoman, "Where's the self-help section?" She said if she told me, it would defeat the purpose
That's actually more hopeful; she may have said it was way too late!
What would we have called the color orange if it weren't a fruit?
Anything strange -- it's too easy to rhyme "yed" or "rellow"
If someone with multiple personalities threatens to kill himself, is it considered a hostage situation?
If he succeeds, is it a mass-murder?
Is there another word for synonym?
You mean, like a verbal alias?
Why is the time of day with the slowest traffic called rush hour?
The angrier you get while stuck in it, the more the blood will rush.
No one is listening until you make a mistake
Not usually true; no matter what you're excuse, they'll rarely be listening then.
Sorry that I haven't been entirely helpful with many of these.