What chain of discount stores last operated in 1990 and used Mammoth Mart for their prototype?
Mammoth Mart: Mammoth Mart was a discount department store chain, located in the northeastern United States, primarily in the New England area. Mammoth Mart:  Other discount department store retailers like K-Mart, Zayre, and Bradlees would subsequently expand on this concept. Zayre: Zayre was a chain of discount stores that operated in the eastern half of the United States from 1956 to 1990.
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