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A hamburg quick-service restaurant may need only a popluation of 5000 to support it, while a polynesian restaurant might require 200,000. A casual restaurant may do well with only a few thousand potential customers, while a gourmet may need 100,000 people in its potential market. The marketing manager for one upscale dinner house chain feels that a population of 250,000 within a 5 mile of one of their restaurant is needed for support. If the unit is located on a freeway, the radius might be extended to 10 miles.