Babylon, Perseoplis, and Susa.
Explanation:
the most complex energy system is the aerobic or oxygen energy system which provide mass of the body's ATP
The command economy is controlled by a central force like the government. Market economies are controlled by market forces
Answer - Three factors fueled American Imperialism.
Economic competition among industrial nations.
Political and military competition, including the creation of a strong naval force.
A belief in the racial and cultural superiority of people of Anglo-Saxon descent.