Yeah, I can see the lines on the shoulder, that's why I asked. I would think if it doesn't have red or cinnamon feathers on its breast/vent, then it is probably a hen. But you might just have to wait till it lays an egg to know for sure! Sorry, I'm not much help!
Does that last one have any colored feathers on its breast? Like red or cinnamon colored? I have one male like that that has no bib, but he does have a light cinnamon coloring to his chest.