Which of the following is not a subsystem of earth’s hydrologic system? groundwater glaciers mountains atmosphere

mountains

Explanation:

Hydrological system of earth is the hydrosphere. It consists of total amount of water present on earth. The water is present in the atmosphere in the gases form (water vapor). The water accumulates in the geosphere is the groundwater. Glaciers are the sources of water in the solid form of ice.

Mountains are not the part of hydrological system.

answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

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