Answer:
Chinese historians have spent well over a thousand years trying to understand why the Han Dynasty collapsed. Over time they developed three main theories: 1) bad rulers; 2) the influence of empresses and court eunuchs over child emperors too young to rule by themselves; and 3) the Yellow Turban Revolt.
Explanation:
The Nile River.
Hope this helps.
The Federal Government of the United States (U.S. Federal Government) is the national government of the United States, a constitutional republic in North America, composed of 50 states, one district, Washington, D.C. (the nation's capital), and several territories. The federal government is composed of three distinct branches: legislative, executive, and judicial, whose powers are vested by the U.S. Constitution in the Congress, the president, and the federal courts, respectively. The powers and duties of these branches are further defined by acts of Congress, including the creation of executive departments and courts inferior to the Supreme Court.
I believe the answer is 4. During the reign of Askia Muhammad, the Songhai empire reached its greatest size.
Askia Muhammad was an emperor, military commander, and political reformer of the Songhai Empire in the 15th century. His rule resulted in trade with Europe and Asia, building of lots of schools, and spread of Islam through his empire.
Hope this helps! Please let me know if I'm wrong :)
A cause would be the arrival of the Portuguese on the coast of Benin