Answer:
The solar mass ( M ☉) is a standard unit of mass in astronomy, equal to approximately 2×1030 kg. It is often used to indicate the masses of other stars, as well as stellar clusters, nebulae, galaxies and black holes.
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Explanation:
please mark me brainliest
Answer:because people don’t live on water
Explanation:
around the equator is still hot, we just aren’t mermaids so we don’t live there.
River valley trade made them key economic areas.
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