hi can anyone tell me when i can let my chicks now 9weeks old out with the rest of the gang we have avariety of hens and the surrogate mum is a jasmin

hi can anyone tell me how can i tell what i have in my range of 9week old chicks how do i tell which is a hen and which is a cockerel as i dont think the neighbours would be too pleased to hear a cockerel crowing at 4 in the morning i have 3 blue aracunas and 7 silkies light brown in colour thanks