these three were found motherless outside, and i took them in. (there are wild chickens where i live, mostly just mixed bantam breeds and jungle fowl) id say theyre about a week old maybe a little less.
That was nice of you! We usually start guessing gender at 6 weeks old. I agree that the chicks are mixed. The black one will have barred coloring and the other two will be some variation of brown, probably.