Since orbital period depends on how far you are from the sun, planets closer to the sun have a orbital period less than one earth year.
These planets are Mercury and Venus
Answer:
I think the answer should be B. Number of valence electrons
The correct answer is D<span>) remains hazardous for a long time. Nuclear waste stays radioactive for many centuries.
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This is generally buried underground, so it does not cause significant air pollution, greenhouse effect, or acid rain<span>. These three are mostly caused by particulate matter or greenhouse gases that are emitted into the atmosphere
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