Answer:
Explanation:
thickness of aerosol layer is 2.5 km
zenith angle is 40 degree
we know that
where
is extinction coefficient
extiction cross section
N = Concentration
transimiitance 
Answer:
C. Physical
Explanation:
The Rio Grande river is an example of a physical boundary between two countries since it is a landform. Physical boundaries are very diverse and can include oceans, seas, mountains, rivers, and lakes, just to name a few of the many landforms that can make a physical boundary.
A cultural, geometric or religious boundary could perhaps be visible with the right type of map, but a river does not tell us anything about the religious makeup of a certain area, nor does it reflect the cultural of the inhabitants.
They have a long history of war
The Amazon and the Mississippi river similarities is Both played a role in the development of civilization. Both are key players in the surrounding ecosystems.<span>
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