two stars appear equally bright from earth, but one is much farther away. what can be inferred about the more distant star?
it emits less light than the closer star
it has a smaller mass than the closer star
it has a higher luminosity than the closer star
it is moving toward earth

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# Brief Explanations:
The apparent brightness of a star is related to its luminosity (intrinsic brightness) and distance. The formula for apparent brightness $b=\frac{L}{4\pi d^{2}}$, where $L$ is luminosity and $d$ is distance. If two stars have the same apparent brightness ($b_1 = b_2$), and $d_1<d_2$ (one is farther), then from $b=\frac{L}{4\pi d^{2}}$, we can rewrite $L = 4\pi b d^{2}$. Since $b$ is the same and $d$ is larger for the more - distant star, its luminosity $L$ must be larger.
Mass of a star is not directly related to apparent brightness in the way described by the inverse - square law of brightness. If a star is moving towards Earth, it would cause a blueshift (a change in wavelength of light due to Doppler effect), not directly related to apparent brightness in the context of distance - luminosity relationship. If it emitted less light (lower luminosity), given the same apparent brightness and larger distance, it would violate the $b=\frac{L}{4\pi d^{2}}$ relationship.

# Answer:
It has a higher luminosity than the closer star.

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