I believe it is..
<span>C. Whether it is moving toward us or away from us
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The other ones don't make sense, radiant energy is electromagnetic and gravitational energy. You can't tell how many planets are in its solar system from only this information. The number of galaxies is also impossible to tell. The only other one that could perhaps make sense is the distance to the center of its galaxy. But, this again is disproved as one star can't tell you the position of the center.
They are larger planets, therefore they have larger cores that can give out more heat.
That would be 75% of Earth's atmosphere.
