As the networks know how a lot of viewers are prepared to see their programming?

marimba tuning on plans: concern by JC : How do networks know how several viewers are prepared to see their programming Just curious, how huge networks to measure how several viewers in their a variety of air shows / programming to watch. A lot of thanks Answer greatest: response to IL Mama As a telephone company does not know who called you. I do not know how it operates, but somebody finds out that crap. Enter beneath your answer to this query!

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