Answer:
A. Obsidian
Explanation:
It fits the property described in the question.
It cools so fast that no visible crystal or grain could form. It has high silica Composition, black and glassy. It is also used to make tools with sharp edges
It is covered with a biological community of vegetation composed of
mainly cone-bearing needle or scale-leaved evergreen trees. It is called
"land of little sticks". The forest trees in the taiga grow as tall
as the highest latitudes of other trees in other places.
In the 31 countries at the bottom of the list, 28 of which are in sub-Saharan Africa, a person can hope to live on average only 46 years, or 32 years less than the average life expectancy in countries of advanced human development, with 20 years slashed off life expectancy due to HIV/AIDS.
I think that it was a siege
Answer:The Earth's lithosphere is relatively hard rigid-like whereas, the asthenosphere is relatively hot and plastic-like
Explanation: The surface of the lithosphere has the rocks which can bent but does not flow , that is having rigid nature whereas the asthenosphere has comparatively have a flow in nature and are considered as plastic-natured .The lithosphere is segmented into rigid plates that are present on top of the flowing asthenosphere.
It is stated that the hard rocks don not flow while the flow can be seen in the plastic -like rocks.