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Question
If Vega is apparent magnitude zero, and Deneb first magnitude, thenA) Vega is about 100 brighter than Deneb.
B) Deneb is one magnitude brighter than Vega.
C) Vega is 2.5 brighter than Deneb.
D) Deneb must be a main sequence star, and Vega a giant.
E) Vega must be 2.5 hotter than Deneb.
Answer
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