Best Seo Link Style

Hello guys,
I need to know one thing to find the best seo link style.
I would like to know what is better to use between these two kind of links for .jpg image file and .flv file.

Example for a flv file:
1.http://***.***.***/files/videos/study-video-378.flv or
2.http://***.***.***/files/videos/2009-08-30-study-video.flv
3.http://***.***.***/files/videos/2009-08-30-study-video.wmv.flv

So, what is more seo?

Thanks