*science* along with earth’s crust, which portion of the upper mantle forms the lithosphere? a. cooler, more rigid outer portion b. hotter, liquid-like inner portion c. cooler, liquid-like inner portion d. hotter, more rigid outer portion

The correct answer is option A, that is, cooler and more rigid outer portion.

The lithosphere of the Earth comprises the crust and the uppermost mantle that forms the rigid and hard outer layer of the Earth. The lithosphere is sub-differentiated into tectonic plates. The topmost section of the lithosphere, which chemically reacts with the hydrosphere, atmosphere, and biosphere via the soil producing procedure is known as the pedosphere. The lithosphere is situated above the asthenosphere that is the hotter, weaker, and deeper component of the upper mantle.  

A = cooler, more rigid outer portion

Explanation:

Plato answer is A

the answer for sodium is 0.186

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