1. During the Song dynasty, Chinese farmers fed nearly 100 million people through innovations like importing fast-ripening rice and allowing two crops per season. This fueled population growth. 2. Trade within China and abroad made the country richer, as cities grew and goods were shipped on rivers and barges. Merchants traded food from farms and other goods like cotton, tea, and processed textiles. 3. Scientific and technological advances included adopting algebra and the concept of zero in mathematics, inventing movable type printing, and developing gunpowder. These contributed to cultural and economic growth during this period.