Answer: Hard
Explanation:
The upper part of the mantle is hard as it contains thick rock layers. The mantle's upper layer and the crust make up a brittle and rigid rock that's referred to as the Lithosphere.
The upper mantle starts below the Earth crust and then stops at the start of the lower mantle. We should note that the upper mantle results in the movement of the tectonic plates.
Water's extensive capability to dissolve a variety of molecules has earned it the designation of “universal solvent,” and it is this ability that makes water such an invaluable life-sustaining force. On a biological level, water's role as a solvent helps cells transport and use substances like oxygen or nutrients.
