The Kansas-Nebraska Act was supported by and seen as an advantage to white people in the North
border ruffians from Missouri.
supporters of slavery in the South

supporters of slavery in the South

Explanation:

Why did Southerners support the Kansas-Nebraska Act? The Popular Sovereignty clause in the Act meant the territories might allow slavery and enter the Union as slave states. The population increased greatly as settlers flooded into the territory from both free states and slave states.

these civilizations were located around fertile rivers, where they could produce an abundance of crops

equal area projections

equal-area projection. a projection in which regions on the earth's surface that are of equal area are represented as equal.