Can $2/click ads and 2cent ads co-exist in the same ad unit (content), on the same page, at the same time? I thought it was impossible because the keywords they bid should be similar and should cost about the same, but I've seen some interesting stats on the web that made me wonder. Thoughts?
You could have a $100 and 1cent in the same ad. If there isn't enough high paying ads the lower value ones will be added in.