Red sexlinks will feather in red with some white. Rhode Island Reds should feather in solid red with maybe some black lacing. The broilers will be twice the size of everyone else in a couple weeks. In two more weeks, it should be obvious who is who.
One of your leghorns looks like a possible cockerel, and the last chick is definitely a cockerel. Barred rocks and red Sexlinks are definitely pullets.