Black Sumatras hens or roaster

I have 3 Black Sumatra chickens. They are 13 weeks old. I at first thought they were all hens but now one of them has started to get long tail feathers. So now I am not so sure. I have looked at lots of pictures online and it seems hard to tell. Please Help me figure it out
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Here is the one that I am not sure about. I think the tail feathers are starting to look like a roaster.


This is one of the other ones. I think this one is a hen.


This is the other one I think is a hen.


This is another picture of the one i think is a roaster.

 

Thanks the top and bottom picture are the same bird, so just one roaster.