What were the labor systems like in the song dynasty?

For over three centuries during the Song dynasty (960–1279) China experienced sustained growth in per capita income and population, structural change in the economy, and increased pace of technological innovation. ... In north China, the main fuel source for ceramic kilns and iron furnaces shifted from wood to coal.

ur mom

explanation:

no statements but ok.

the statement that best describes the idea of manifest destiny that was used in the 19th century would be that "it was fate that the united states would continue to  expand westward," since people thought the us was "destined" to do so.