Answer:
The wealth of the states came from controlling the trade routes across the desert. Their power came from having large pack animals like camels and horses that were fast enough to keep a large empire under central control and were also useful in battle.
Explanation:
wiki
He conquered China, and the made his own dynasty.
The photograph.
Because it is made by someone other than Rosevelt but it is still first-hand information.
Steam boats, rail roads and telegram made communication and work easy and faster.
