Probably a stupid question... about Finder in Mountain Lion

Hi, I was just fiddling with being able to move the categories in the finder sidebar and I tried to move the 'devices' category to the top. Instead the 'devices' category vanished and the items in that category got added into 'favorites'.
Question #1: How do I get that category back???

Then, when I was trying to fix that, I dragged the usb stick I had plugged in to the top, but accidentally put it into the top part of the finder window instead! Now when I ejected it a question mark sits there at the top, and I can't get rid of it.
Question #2: How do I get rid of the question mark???

I attached a pic of what I see in Finder.
Please help, thanks.

 

Well, crap on a stick. Thank you! There's question #2 answered

Anyone able to help me with Question #1? Gracias

 

Awesome! Thanks to both of you for the quick help! Much appreciated