I have an interesting question??

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Sounds to me like they are paying more for "lessons" from you, than you paid for the books. Let them keep paying. I was in a similar situation with guys I work with. They even started to suggest I might be cheating. I pointed out to them that I was the only one of the bunch that doesn't drink. Also I read books, watch vids and play online. They started drinking less and paying attention, most of them have gotten better.

peace.
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