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: Which tree belongs to the genus Betula?

Answer: birch


Question: Romania and which other country joined the EU on the 1st January 2007?

Answer: bulgaria


Question: Orchestral conductor Leopold Stokowski was born in 1882 in which capital city?

Answer:
london