Uhm....Adwords is something you pay for in order to attract visitors to your website. You pay for adwords and the ads appear as adsense ads on other peoples websites and in the SERP.

not adwords, but adsense.
yes, it really can bring you some cash if you have some thousands of traffic on your site daily

Yes, Its Addsence.. even through i have tried many times to register with this i have rejected.. even i have high quality content on my site.. so before add them read the TC very closely

Yes this is really give you some awesome results,if you have great traffic on your site. I think this is the best way to earn money. I have been using this for one year and i got very sensational results.

In my experiences, Google AdWords is good tool and way for business online.Excellent keywords tools for you market positioning.And they can bring customers for all of the world.