Precambrian rocks<span> are mostly covered by rock systems of more recent origin, but where visible they commonly display evidence of having been altered by intense </span>metamorphism<span>. Precambrian rocks often occur in shields, which are large areas of relatively low elevation that form parts of continental masses.</span>
The correct answer is - 3. maize.
The maize was the basis of the diet of the civilizations of Mesoamerica. It was one of the first wild plants in which the people from this region saw a potential as a big and stable food source, so they started to farm it. All of the civilizations we know from this region, like the Olmecs, Toltecs, Mayans, Aztecs, formed and developed their civilizations around the food source that was provided by the maize.
Answer: Most of the world's volcanoes are found around the edges of tectonic plates, both on land and in the oceans. On land, volcanoes form when one tectonic plate moves under another. Usually a thin, heavy oceanic plate subducts, or moves under, a thicker continental plate.
Answer:
B
Explanation:
The printing press allowed mass production of books that spread new scientific ideas.
It has gone through four half-lives of carbon-14 (5730 years<span> x 4 = </span>22920 years<span>)
It is 22920 years old.
Hope this helps!</span>
