Ignoring "Baron Max"'s slightly insane ramblings... Every (young) engineer knows wikipedia is a great source of information.
Yes and no. Part of the problem is a correlation difficulty: just that kids likely to try marijuana are likely to try other things as well. But I...
I don't think we know the chemistry. But as others have said there are a very large number of explanations. For me personally, I fidget like none...
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