You see two main-sequence stars with the same spectral type. Star 1 is dimmer in apparent brightness than Star 2 by a factor of 100. What can you conclude, assuming there is no absorption of either star's light by interstellar gas or dust?
A) Without first knowing the distances to these stars, you cannot draw any conclusions about how their true luminosities compare to each other.
B) The luminosity of Star 1 is a factor of 100 less than the luminosity of Star 2.
C) Star 1 is 10 times more distant than Star 2.
D) Star 1 is 100 times more distant than Star 2.
E) Star 1 is 100 times nearer than Star 2.
C
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