Answer:
This is a primary source, namely a written one, because it derives directly from the past and its content hasn't been alternated.
Explanation:
Historians are dividing sources into primary and secondary. Primary sources are derived directly from the past, meaning that they are created at the time when some event happened. This is an example of primary source, as it is an original letter that one ruler sent to another one.
Answer: One by one, the Classic cities in the southern lowlands were abandoned, and by A.D. 900, Maya civilization in that region had collapsed. Finally, some catastrophic environmental change like an extremely long, intense period of drought–may have wiped out the Classic Maya civilization.
Explanation:
Answer:
a,b,c are correct... take for example Indus valley civilization