How to remove obsolete/old questions from list /unanswered?by=selected ?

Question

I'd like to remove old questions (let's say 2 weeks old) from the http://www.question2answer.org/qa/unanswered?by=selected list.

How should I do it? =)

 

PS: Just see that the URL is kind of misleading /unanswered?by=selected → as it shows answered questions as well!

Comments

Regarding your last sentence, it's just another definition of "unanswered" ;)
You could say it means "the user has not selected a best answer, therefore the question has not been fully answered".