You measure Cepheid variables in galaxy A and galaxy B. Both Cepheids have the same period, but the one in galaxy B appears 16 times brighter than the other. You conclude
A. Galaxy B is 16 × 16 = 256 times more distant that galaxy A.
B. Galaxy A is 16 × 16 = 256 times more distant that galaxy B.
C. Galaxy A is 4 times more distant than galaxy B.
D. Galaxy B is 4 times more distant than galaxy A.
E. Galaxy B is 16 times more distant than galaxy A.
Answer: C
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