How to change a Discussions post to a Question

[Akeif]

I've opened two discussions recently but they really happen to be more like questions. They were both answered but both posts are still opened :

http://www.seomoz.org/q/reading-suggestions-for-a-local-french-small-biz-website

http://www.seomoz.org/q/should-i-block-wordpress-archive-and-tag

How can I change them back to Question so I can mark them as close?

Thanks

[Unity]

Go to the post, click edit and at the bottom of the page there is two radio buttons where you can select 'question' or 'discussion'.