Your question doesn't make much sense :) If by "standard" you mean the way the Q2A files are distributed then there is no answer to that question because Q2A is distributed as a zip file and zip files don't save file permissons on them as tar files do.
Now, if you're talking about how things were before you change them, then it is impossible to know as it is just a matter of configuration which should reflect an intention which you haven't mentioned. EG: If you want to add files to a directory then you need to be able to write to it. Not to mention it also depends on what user you are and what groups are you part of in order to provide appropriate privileges.
Answering in general terms, and without taking any other consideration, 755 (or even 750) for directories and 644 (or even 640) for the rest of the files should be fine. I believe you can even get away with a 755 for directories in which you are storing uploaded files as the PHP process runs as the owner of the files.