Hello,
My question concerns ebooks and to a less extent, copyright law.
As far as I can tell copyright law applies differently to these
types of ebook "rights":

- Reprint rights.
- Resell rights.
- Resale rights.
- Master reprint rights.

My question is - am I allowed to take an existing ebook with complete
"rights" and then publish this ebook as a group of pages on my
website. In other words, the pages of the ebook, become full text
pages on my website. Is this legal if I own the resell, reprint,
resale, or master reprint rights to a given ebook.

Also, is it possible to publish a certain percentage (perhaps 10%) to
fall into the fair use policy? Ultimately, I would like to profit by
displaying Adsense advertisments beside the pages of the ebook that I
have publishing online as normal webpages of a website.

I'll let one more knowledgable than I (and an offiical GA researcher)
answer to the main point but as for this:

"Also, is it possible to publish a certain percentage (perhaps 10%) to
fall into the fair use policy?"

I'll just point out that Fair Use is purposefully defined vaguely so
that, really, every case has to be judged on its own merits. But
realize that there is no set percentage, no magic ratio that
determines that if you use X amount of a work, it qualifies as Fair
Use, but if you use X + 1 amount, that's not Fair Use.