What breeds are these chickens

[newchickmom09]

These were our first chicken that were given to use from a friend when they didn't want to take care of them anymore. They never told us what breeds they were or how old they were so the age is a guess for me. The black ones are two roos and the brown ones were two hens.
Here they are when we first got them after a bath (4 weeks old):

About 7 weeks old:

Then the two roos at about 4 months old:

 

[barred-rocks-rock]

The red ones are sex links and the black ones are australorps or jersey giants. all of them are hens

 

[speckledhen]

Red sexlinks and probably black Australorps.

 

[Elite Silkies]

The black ones are Australorps.

 

[pattypenny]

2 red sex links and 2 black australorps.

 

[newchickmom09]

thanks everyone, I was thinking red sex links after doing some research. The black roos are the ones that had me stumbed since I am still new to the chicken seen.

barred-rocks-rock~ the black ones are defiantly roos, they started crowing at 3 months old and mastered it at 4 months old. Thats why we don't have them anymore.