Theories about what caused the Classic Maya collapse have ranged from overpopulation to ongoing military conflict between competing city-states to some catastrophic environmental event, such as an intense drought—or some combination of all of those factors.
It’s the third one because that’s the only INTERNAL conflict.
A production possibilities frontier, or PPF, shows the D. maximum amount that an economy can produce. It is shown in a graph as a curve, and if the economy is shown as below the curve then they are operating inefficiently.
Answer:
Carbonization
Explanation:
the process is called Carbonization