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Question
When a low mass star first runs short of hydrogen in its core, it becomes brighter becauseA) it explodes as a nova.
B) helium fusion gives off more energy than does hydrogen.
C) its outer, cooler layers are shed, and we see the brighter central core.
D) the core contracts, raising the temperature and extending the hydrogen burning shell outward.
E) the helium flash increases the size of the star immensely.
Answer
This answer is hidden. It contains 1 characters.
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