What led to the population increase in china during the tang and song dynasties?

Explanation:

The population of China doubled in size during the 9th, 10th and 11th centuries. This growth was made possible by expanded rice cultivation in central and southern Song, the use of early-ripening rice from south-east and southern Asia, and the production of widespread food surpluses.

answer

the statement that best describes president carter’s attempt to free the hostages in iran is c. all of the attempts failed.

explanation

the operation eagle claw conducted by the united states armed forces was a failed mission which aimed to rescue 52 americans captured as hostages in the american embassy, tehran on 24/4/1980.the mission was authorized by president jimmy carter. the failures included;   obstacles in operation that included operational conditions challenges caused by sandstorms, hydraulic problems of one the helicopters and , mechanical failure of another helicopter that was identified as a cracked rotor blade and the crashing of another helicopter during mission abortion causing death of 8 service persons.

answer; professor;