Multiple Choice
When does a star achieve hydrostatic equilibrium?
A) when it becomes a main-sequence star
B) when it leaves the main sequence
C) when it becomes a protostar
D) This question has different answers for stars of different masses. Massive stars never achieve equilibrium; small stars achieve hydrostatic equilibrium as soon as they reach the main sequence.
Correct Answer:

Verified
Correct Answer:
Verified
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