Question

Red giants are smaller than main sequence stars, which are smaller than white dwarfs.

A.) True

B.) False

Answer 1

False. A Red Giant evolves from a main sequence star after it commences Helium fusion and undergoes a great expansion; in the case of our Sun it would expand to encompass Earth's orbit. Thus, it would have approximately the same mass (a small amount being expelled in the helium flash), and vastly greater volume, equating to vastly lower density.

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