Generate a correct and concise answer for the question based on the words in the context.
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Question: Context : Used by the U.S. Army, the U.S. Marine Corps, as well as many foreign militaries, the M47 Dragon was first fielded in January 1975 to U.S. Army soldiers stationed in mainland Europe.
Question : What year did M47 Dragon come into use?

Answer: 1975

Question: Context : OPML (Outline Processor Markup Language) is an XML format for outlines (defined as ''a tree, where each node contains a set of named attributes with string values'').
Question : Which is the basis of OPML?

Answer: XML

Question: Context : HD 82943 (164 G. Hydrae) is a yellow dwarf star approximately 89 light-years away in the constellation of Hydra.
Question : What is the constellation where HD 82943 is located?

Answer:
Hydra