The answer would be "the boiling and freezing points of water."
Answer:
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Greenhouse gases are certain molecules in the air that have the ability to trap heat in the Earth's atmosphere. Some greenhouse gases, like carbon dioxide (CO2) and methane (CH4), occur naturally and play an important role in Earth's climate. If they didn't exist, the planet would be a much colder place.
Explanation:
The DNA is found in the nucleus of the cell
Answer:
C is not sprial galaxy i think
The answer is B. It is B because in if convection currents cooled down then the earth would die.