chickentvforme
Chirping
These are 8 week olds.
You'll need to take better, individual pics of each bird. A side profile and a straight on shot so we can see their combs (it would be very helpful to pull the Polish's crests back so we can see what's going on there).
As for guesses based on what I can see, I'm thinking both of the Polish are cockerels since they're already sporting those large red wattles. I'm not too sure on the Cochin, its comb doesn't look red or anything, but it appears sizable in the pic.