Multiple Choice
Why do O- and B-type stars have weaker hydrogen absorption lines than A-type stars?
A) O- and B-type stars are cooler than A-type stars.
B) A larger fraction of the surface hydrogen atoms in O- and B-type stars is ionized.
C) O- and B-type stars have converted much more of their hydrogen into heavier elements.
D) A-type stars have a higher mass than O- and B-type stars, and they have more hydrogen.
Correct Answer:
Verified
Correct Answer:
Verified
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