Which of these pieces of legislation was an important step in limiting slavery?

Although a number of things brought about world war one there was one even that push to europe over the edge. what was that event?

Which german count invented the zeppelin

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