It looks like you have Cornish Crosses They are generally butchered when they are around eight weeks old and if you choose not to butcher them they won't live much longer than that. Also the front two look like cockerels and I need better pictures of the others.
If they are Cornish I'm a little ****** told the lady I was getting them for eggs. I've looked up pic of the white rock and Cornish and all the Cornish I saw was all white. The white rock some where all white and some where different colors. Some of mine have a few black feathers. The day I went to TSC all they had was stright run.