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Which source would best a historian understand the effect of the great chicago fire on families? a. a biography of a chicago family displaced by the fire b. a letter from a grandmother in new york to her family in chicago c. a newspaper editorial about families who were displaced d. an oral history dictated by an adolescent who fled the fire

Which statement is true of both presidential and parliamentary systems of government?

Why would the free rider problem prevent a private business from investing in the building of a city sidewalk?