It's tough to see the comb on that one, but from what I can see it still looks very pale. I think they are all pullets. At 5 weeks of age a cockerel would have a reddening comb and wattles.
oh yes, we have a bigger brooder i had them in the smaller one trying to clean out the bigger one, they grow so FAST, lol...
hopefully once the weather gets better they should be outside SOON