<em>Hello there, and thank you for posting your question here on brainly.
What event caused World War 1?
<u>Answer:
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<u>The event that caused World War 1 to start was the assassination of Archduke Franz Ferdinand on June 18th, 1914. World War 1 started a month later.
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Hope this helped you!! ♥</em>
Answer: They help to clarify what happened in a crime.
Explanation: Witnesses tell the judge and/or jury everything they know about an event. A witness is someone who has <em>relevant information</em> about a crime that had taken place.