The farmer had all the answers about the cows.

Interviewer: How much milk do these cows give?

Farmer: Which one? The black one or the brown one?

Interviewer: Brown one.

Farmer: A couple of litres per day.

Interviewer: And the black one?

Farmer: A couple of litres per day.

Interviewer (naturally a bit flummoxed): I see. What do you give them to eat?

Farmer: Which one? Black or brown?

Interviewer: Black.

Farmer: It eats grass.

Interviewer: And the other one?

Farmer: Grass.

Interviewer (now annoyed): Why do you keep asking which one when the answers are the same?!

Farmer: Because the black one’s mine.

Interviewer: Oh, and the brown one?

Farmer: It’s also mine.