Given an trivia question precisely answer the question with a word/phrase/name. External resources such as Wikipedia could be used to obtain the facts.
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Question: According to Greek mythology, who is the god of war?

Answer: ares


Question: Which cult/religion was formed by science-fiction writer L. Ron Hubbard?

Answer: scientology


Question: The world's first iron bridge was completed in 1781 at Coalbrookdale, which river does it span?

Answer:
river severn