Those with the red combs are roosters. I can't quite see everyone clearly in your photos, but I believe I see two for sure.
That's what I thought too. I didn't take any comparison photos but the one you see in this pic is the one I believe to be a rooster. They all came out of a pullet bin but this one has had red huge comb and wattles since like 3 weeks. The rest are just now getting theirs..