I'm confused by the _META

The %# seem to vary each time it is used - see below. By looking at the actual emails it was possible to decipher what is what.

I have two questions:

#1 is there a place to see what is what and used where? (so it can be changed)
#2 where is it defined that the link to the question or answer is an actual link? >>> REASON: I may need to change the link and point to a different location alternatively be able to add my own meta tag which needs to be a link.

Thanks
L

_QUESTION_META="Posted in %1$s, asked by %2$s, %3$s. %4$s hits."

Posted in %1$s
asked by %2$s
%3$s <--<--< ??
%4$s hits


EMAIL_NEW_QUESTION_CONTENT

<p>A question is asked by %1$s on %5$s.</p><p></p><hr><strong>%2$s</strong><br>%3$s<hr><p></p><p></p><div>You can view the question at the below location:</div><div>%4$s</div><p></p><p></p><div>Have fun interacting with friends and other members on our Community Answers site..</div><div>The %5$s Q&amp;A Team</div><p></p>

asked by %1$s
site name %5$s
question title %2$s
question text %3$s
link to question %4$s
site name %5$s


EMAIL_NEW_ANSWER_CONTENT

<p>The question <b>%1$s</b>, asked on %4$s, received a <strong>new answer</strong>.</p><hr /><p></p><p>%2$s</p><hr /><p>You can view the new answer here:</p><p>%3$s</p><p></p><div>Have fun interacting with friends and other members on our Community Answers site.</div><div>The %4$s Q&A Team</div><p></p>


The question %1$s
asked on %4$s
new answer %2$s
view answer here %3$s
site name %4$s