In this task, you're given an open-domain question. Your task is to provide an answer to the given question. There is only one unique answer for each question. Your answer should be short, and refer to an entity, date, number, etc. Do not put your answer in the context of a sentence.
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Question: Journal of optics a pure and applied optics abbreviation?

Answer: J. Opt.


Question: Where does the last name dumas come from?

Answer: Southern French


Question: Who is long john silver in black sails?

Answer:
Luke Arnold