The inventions I have read about are catapults, trading, ships, tributary, and block printing. Catapults launched large, heavy rocks to break down city borders / walls, these were commonly used in war. This also inspired those who had them to make bombs out of gunpowder. New crops like cotton and tea, silk, spices, and other rich goods were used for trading at the time. Ships were used for across sea trading, travel, and Mongols used ships to trap cities along southern China's rivers. Tributaries were used to give gifts to more powerful countries, this prevented attacks / wars and kept the walls of China at peace. Finally, block printing first started by making books, books helped with schools and authors publishing their work.
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