What airmass and source regions provide the greatest amount of moisture to the eastern and central United States

In what climate does shifting cultivation predominate? and, what are its two characteristics?

Summarize the president's/vice president's roles and responsibilities in 8 sentences

Mexico city is an example of how humans alter their environment because it was a. one of the world’s largest cities b. built on drained and filled lake beds c. built after conquest by the spanish d. once the capital of the aztec empire