Any ideas on a breed for this gal? (came from someone who got a "mix")

[obmarriott]

Took the plunge, but knowing that we couldn't do new hatchlings I went for pullets. But the people I got them from weren't "sure" of breed (I guess they got a "mixed batch" of female 1 day olds). So the lady said the smallest (at top in the pic) is a Partridge Rock, but she didn't know about the black/brown one (medium sized and at the bottom). I got the big one (Ameraucauna) from a different person. So, if you experts have any thoughts I'd love it. I tried to look through pictures, but I just keep getting distracted by so many adorable birds!