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
Answer:
An agronomist works in the field of agriculture, and acts as the go-between for farmers and crop researchers. Agronomists have a wide range of work, but their role is best summed up as a “crop doctor.” They are concerned with the health and well-being of crops used for food production, fuel, and land reclamation.
All of the above if you think about it every thing make sense
The correct answer is : Planetary accretion
In Planetary accretion theory, the universe was formed by accretion process, which is the accumulation of particles into a massive object by attracting more matter, forming all kind of astronomical objects such as stars and planets