Multiple Choice
What is a Cepheid variable star?
A) one of several classes of stars that pulsate randomly in brightness
B) low-mass, horizontal-branch star that pulsates regularly in brightness
C) star that normally remains constant in brightness but occasionally flares up in brightness by several magnitudes
D) high-mass star that pulsates regularly in brightness
Correct Answer:
Verified
Correct Answer:
Verified
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