This zone is called as the zone of aeration. It is present between the earth's surface and the water table, and its main constituents are the soil and rocks. The pores which are present in this zone are partly filled with water, and may mix up with air, causing aeration.
Answer:
Both options are valid, since in the hypothesis of the savanna it was argued that humans acquired bipedalism to be able to self-supply their food more effectively, and to have less body surface area exposed to the sun.
Explanation:
The saban hypothesis is believed to have originated in the saban, with the Austrolopitecus africanus being forced to affect this domain, which is why it acquired this adaptation mechanism.
The savanna had high grasslands, which also led to collaboration in this regard since they could be better camouflaged.
In addition, the human began to defend with the limbs of the upper limb, triggering the canines to decrease in size since it is not used as a defense mechanism.
The canine is a tooth that helps to tear carnivorous food, that is why the human also begins to have a more varied diet of fruits and seeds and that it can reach and take the bones of the tree to increase its height due to bipedalism.
Answer:

Explanation:
Hello,
In this case, the pH is computed by:
![pH=-log([H^+])](https://tex.z-dn.net/?f=pH%3D-log%28%5BH%5E%2B%5D%29)
Whereas the concentration of hydrogen ions equals the concentration of the acid for strong acids such as hydrochloric acid (HCl) due to its complete ionization in solution, which means that such concentration is 0.00125 M. Thus, the pH turns out:

Regards.
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I know I am not supposed to post links but, I found help
Answer:
Change in the vascular system.
Explanation:
High blood pressure occurs when the arteries in the human body system become rigid thereby making the blood pressure rise.
The cause for this situation particularly in older people is the changes in the vascular system or circulatory system.
This is said to be vasoconstriction which lowers the flow of blood in the circulatory system, thereby causing high blood pressure
Hence, since Mr. Ackah is a retired teacher, it is believed that he is an old man susceptible to changes in the vascular system or vasoconstriction.