#nav-bar li:hover ul not working?

[wvusakf]

My following css selector \[code\]#nav-bar li:hover ul\[/code\] should show the \[code\] <li><a href="http://stackoverflow.com/questions/8450754/#">Marketing</a></li> <li><a href="http://stackoverflow.com/questions/8450754/#">Advertising</a></li> <li><a href="http://stackoverflow.com/questions/8450754/#">Media</a></li>\[/code\]but its not showing here is the fiddle http://jsfiddle.net/g9Rrn/1/