Which item is an example of a primary source?

In 2001 mexico imposed a 20% tax on all soft drinks not made from sugar cane high fractals corn sit-up which is made from corn, is often used in place of cane sugar to manufacture soft drinks. which nation would most likely be impacted by mexico’s policy change?

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

Dalton developed the first model of the atom that showed the structure of the inside of an atom