Answer:
period of disunion= China faced constant threats and attacks from nomadic tribes and groups, such as the Huns,
and Various small kingdoms that were always at war with one another ruled China.
-----------------------------------------------------------------------------------------------period of union= The philosophy of Neo-Confucianism led to the formation of a new class of bureaucrats, and
The Chinese invented paper money, the compass, gunpowder, and the water-powered clock.
hope that helps I got a 100 on this test so I know that it is correct