That all depends on the breed. Are you asking about a dairy cow or a beef cow, and what breed of dairy or beef cow?
The Jersey is the smallest dairy cow, but not thesmallest breed of cow. The Dexter is the smallest breed of bovine.
they make dairy products
Yes.
Charolais is the best beef breed, and Holstein is the best dairy breed.
Jersey
You are probably thinking of the Guernsey breed.
They are a breed of bulldog, they are white with black spots (like the Holstein dairy breed).
That all depends on her breed and her body type. If she typically looks thin and sports a large udder between her legs, then it's likely that she is a dairy cow. If she is more blockier, not quite as thin and sports a smaller udder, then she would be a beef cow.
Holstein cows are the largest breed of dairy cow they can reach 66 inches tall at the shoulder.
The Guernsey's.
Ayrshire animals are a breed of dairy cattle, known for their red and white markings. They are popular for their high milk production and adaptability to various climates.