A man was seated next to a little girl on the airplane when he turned to her and said,

'Let's talk. Flights go quicker if you strike up a conversation with your fellow passenger.'

The little girl, said to the man, 'What would you like to talk about?'

Oh, I don't know', he answered, 'How about nuclear power?'

'OK', she said. 'That could be an interesting topic. But let me ask you a question first.

A horse, a cow, and a deer all eat grass, the same stuff.

Yet a deer excretes little pellets, while a cow turns out a flat patty, and a horse produces clumps of dried grass.

Why do you suppose that is?'

The man thinks about it and says, 'Hmmm, I have no idea.'

So the girl says, 'Do you feel qualified to discuss nuclear power when you don't know ****?'