4 week old chicks, Mixed breeds?

[NewChickMomma22]

For a class project, eggs were donated to me to incubate. I have 3 four week old chicks now. Any ideas about breed or genders? Also, their feathers are coming in "rough." Is this normal?

 

[BantamLover21]

So far, they all look like pullets. Their feathers are coming in just fine.