Horizontal-Branch Stars Have a Wide Range of Temperatures and Luminosities

question 7

Multiple Choice

Horizontal-branch stars have a wide range of temperatures and luminosities between 50 and 100 times that of the Sun,so they are in what stage of their lives?

• A) gravitational contraction before the start of core hydrogen burning
• B) hydrogen-shell burning, with a degenerate helium core
• C) core helium burning
• D) core hydrogen burning

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