Early civilizations changed their natural environments by: A. draining all the water out of large rivers.
B. using terrace farming to make the soil more fertile.
C. using slash-and-burn agriculture to help forests grow.
D. digging canals to control the flow of rivers.

the compromise of 1850 was a package of five separate bills passed by the united states congress in september 1850, which defused a four-year political confrontation between slave and free states on the status of territories acquired during the mexican–american war

the roman empire began to fall