Question: I'm running F17 and inside of `yum.repos.d`. I see multiple repos listed like `adobe-linux-1386.repo`, `fedora.repo`, `google-chrome.repo`, etc. When I `yum install` are some files being downloaded from multiple different repos or all from one?

Answer: 
Most packages would be downloaded from fedora.repo. Adobe packages would be downloaded from adobe-linux-i386.repo. Google Chrome packages would be downloaded from google-chrome.repo
Also depends on whether a repo is disabled or enabled.