Pocket-knife collector Sam Penley certain to open The Knife Depot a store that sells pocket knives and related paraphernalia. Later 18 months in business Sam has noticed that most of his sales are to the same small group of customers (about 40 people) even still he has records to show there are over 200 active pocket-knife collectors within a 50-mile radius of his store. Sam's retailing experience is supportive of the-