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Question
The key to finding quasar's distances wasA) a Type I supernova in the spiral arm of 3C87.
B) the huge red shifts of the hydrogen lines in 3C273.
C) planetary nebula in M51.
D) the luminosity of 3C52 from the Doppler shift and the Fisher-Tully relation.
E) globular clusters in the halo of M87 in Virgo.
Answer
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