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Industrialization led to the emergence of "big business" when investors started purchasing shares of stock in

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

How do you think entrepreneurs contribute or industry in america? describe your answer.