The atmosphere is a mixture because it contain many types of gases , liquids and solids.
Answer:
the answer is C
Explanation: The deep ocean circulation of water is caused by convection currents in water that allow cold water to rise and warm water to sink.
Both have phosphate-pentose back bone, as well as both have adenine, cytosine and guanine bases.
Nucleic acids also typically contain phosphorous, and nitrogen plays an important structural role in nucleic acids and proteins. The proteins, being made up a diverse set of amino acids, have, in addition to carbon, hydrogen, oxygen, and nitrogen, the elements sulfur and selenium.