That's known as asdsense arbitrage and Google will shut down both your adwords and adsense accounts for doing it. Don't mess with the Google Gods
Correct, promote thru adwords for your content and NOT for your adsense - so adsense is just there to pay you in case surfers decide to leave your site.
yeah, you'll end up getting slapped by google and getting a quality score of 1/10 (not being able to increase it either). Only way round this is to use a lot of good quality content on the landing pages, with some adsense there too