How did the political structure of the African continent change between 1880 and 1914?

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?

Why were chinese american immigrants frequently detained when trying to immigrate through angel island? the rules for immigration were stricter at this checkpoint due to health issues that were prevalent among asian populations at this time. the location of the island was difficult to reach, and ships to the mainland were often prevented from sailing more than once a week. immigration agents were notorious for asking immigrants confusing questions as a means of denying them entry. low wages caused a shortage of immigration officials, so many immigrants had to wait weeks or months before their applications were processed.

Which of these was an accomplishment of the han dynasty? the invention of the seismograph finding a water passage to europe the invention of the ballpoint pen the invention of the abacus