<span>increase while moving left to right within a period and increase while moving upward within a group. </span>
Answer: The half-reactions represents reduction are as follows.
Explanation:
A half-reaction where addition of electrons take place or a reaction where decrease in oxidation state of an element takes place is called reduction-half reaction.
For example, the oxidation state of Cr in
is +6 which is getting converted into +3, that is, decrease in oxidation state is taking place as follows.

Similarly, oxidation state of Mn in
is +7 which is getting converted into +2, that is, decrease in oxidation state is taking place as follows.

Thus, we can conclude that half-reactions represents reduction are as follows.
Answer:
The levels of carbon dioxide (CO2) in the atmosphere are reduced
Explanation:
Tectonic uplift refers to the process by which the surface of the earth slowly rises either due to increasing upward force applied from the plates below the surface or decreasing downward force or weight of objects like melting glaciers acting from above. During uplift, land, as well as the sea floor rises forming mountains, plateaus and volcanic Islands.
During the process of weathering, carbon dioxide present in air combines with rainwater and forms carbonic acid. This acidic rainwater then falls on uplifted mountains and rocks weathering them in the process. Minerals present in the rock such as calcium, magnesium and sodium then combine with bicarbonate ions to form carbonates such as calcium carbonate, magnesium carbonate which are found in shells of living and dead organisms and also form rocks such as limestone. In this way, carbon dioxide is removed from the atmosphere.
Nitrogen can make bonds with other atoms.. Typically though it only makes 3 bonds, so it fills its octet.
The sedimentary rock formed when water deposits tiny particles of clay in very thin flat layers is called limestone.