The first ones are definitely pullets, the last one definitely looks like he might be a roo. But I'm not an expert. And my BO pullets don't have much of a comb at all.
The last one close up comb looks redder than the top one, guess it helps to get a good close up. Middle pic is definitely a hen, the bottom and top is a roo then!
Well I still think they are both hens. This was my buff orp at 14.5 weeks old. Laid an egg at 20 weeks. Need to look at the hackle and saddle feathers in the teenage birds, not just the combs and wattles. Does the bird have any pointy feathers growing in? I was able to part my hens hackle and saddle feathers when I took this picture and she had nice blunt feathers coming in.