Religion, political, and economy
Answer:A
the Incan civilization was known for the impressive waterworks in their city centers. Some of these included canals, fountains, drainage systems, and expansive irrigation.
One example of their advancement in this area is the Incan citadel called Machu Picchu which is said to be "the pinnacle of the architectural and engineering works of the Inca civilization" when talking about its water supply system.
Caused a dramitic decline of indians
C. People in northern states could simply not afford to own slaves. This was because they were poorer than the southern states.
Honestly, any city around a river, or body of water, like Chicago (Lake Michigan) or New York or San Francisco (The Bay). Richmond, VA (James River).
