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Question
Why are star clusters ideal "laboratories" for stellar evolution?A) The combined light of all the stars makes them easier to see.
B) Like our Sun, they lie in the plane of the Milky Way.
C) Their stars are all about the same age, composition, and distance from us.
D) Their stars are all about the same mass and temperature.
E) Their stars are all the same composition and stage in evolution.
Answer
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