Looking for breed ID help

[Groovy Girl Creations]

I'm a newbie to chicken keeping and I'm currently taking over daily care of a flock of chickens. The flock belongs to the owner of the farm we live on but due to health reasons she is unable to care for them any longer. She is currently not on the farm for me to ask about breeds so I'm looking to you guys for some assistance.
Here are some photos of some of the birds in the flock. I've been told the little white one in the second row is likely a leghorn, but I'm not sure. Anyone have any ideas? There are about a dozen of the big white ones, a handful of the brownish ones in the second row. and the rest are dark ones like the bottom picture and the top right picture. There are 4 roosters-The one in the top middle is the pretty boy, I have a nice red one and a grumpy red one, and a dark one. I'm trying to get a decent picture of the other roosters...they aren't quite as photogenic as the pretty boy.

Thank you in advance for any insight.

 

[HappyDuckie]

The first is a cornish x. Fifth one might be a black sex link.

 

[JedJackson]

Yes, the big white one is a Cornish cross.

Next is a crossbred rooster.

Next is probably a black sex link

Next is maybe a white rock pullet and another black sex link.

Next is a black sex link,

The last, the black bird with a white patch, is a mixed breed.

 

[Groovy Girl Creations]

Thank you so much for your insight! I am loving learning about these birds and appreciate your replies!

 

[SBFChickenGirl]

Yes, the big white one is a Cornish cross.

Next is a crossbred rooster.

Next is probably a black sex link

Next is maybe a white rock pullet and another black sex link.

Next is a black sex link,

The last, the black bird with a white patch, is a mixed breed.

X2

 

[HeatherKellyB]

The black one looks like a Marans cross, which Hoover's Hatchery named Midnight Majesty Marans. Are you getting some large dark brown eggs? I was thinking white Rock for one of the other pictures

 

[HeatherKellyB]

Looks like you are taking over a very beautiful flock! I wish you the very best with them.

 

[HappyClucker7]

Yes, the big white one is a Cornish cross.

Next is a crossbred rooster.

Next is probably a black sex link

Next is maybe a white rock pullet and another black sex link.

Next is a black sex link,

The last, the black bird with a white patch, is a mixed breed.

X3

 

[Groovy Girl Creations]

Looks like you are taking over a very beautiful flock! I wish you the very best with them.

I love them already! They are a lot of fun!

 

[Groovy Girl Creations]

The black one looks like a Marans cross, which Hoover's Hatchery named Midnight Majesty Marans. Are you getting some large dark brown eggs? I was thinking white Rock for one of the other pictures

I have been getting some very large brown eggs. Varying shades from a light tan to almost a dark caramel brown. I have been getting several lately with multiple yolks. A lot of double yolks and even a four yolker! Is that normal?