Tom, president of a local TV station (a Fox affiliate) in San Antonio, TX, recently conducted a study of TV viewers in his area. He obtained a list of all residential customers from the cable company (e. g., a billing list). He put every customer name on a note card, and mixed them up in one raffle barrel. He then chose 1,000 note cards (out of a possible 50,000 customer cards). A trained interviewer visited each household and asked detailed questions about the viewing habits of various family members. How large is his sampling ratio