Answer:
The Neutrality Act of 1937 did contain one important concession to Roosevelt: belligerent nations were allowed, at the discretion of the President, to acquire any items except arms from the United States, so long as they immediately paid for such items and carried them on non-American ships
Explanation:
"To accommodate for lack of dependable rainfall" would be the best option as to why the ancient Chinese organized large groups of people to build and maintain irrigation systems, since when rainfall would not come for long periods of time, the crops would likely die without proper irrigation.
The answer is Mathematics
