The idea that regions are  fluid  means earth’s surface is floating on a hot magma layer formal geographic and political boundaries define a region a region cannot support life without a source of freshwater a region is difficult to define because it is influenced by  people's perceptions and perspectives

I believe the answer is a region is difficult to define because it is influenced by people's perceptions and perspectives.

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the first settlements began along the huang river because of the importance of the huang river in the beginning of china. it goes back to the story, “the tale of emperor yu”, which references the tale of the great flood, which was caused by the huang river and was believed to create and influence china’s making.

the answer is true!