Can you tell the breed?

[CPChickens]

I was hoping someone might have an idea what breeds I have...they are 1 1/2 weeks in this picture....the middle picture chic now has white and black stripes on her side wings.

 

[oldhenlikesdogs]

Speckled Sussex?what type of comb on the first, and second one? Last one looks like a black Cochin.

 

[Gray Farms]

Are they pure breeds or could they be crosses?