Final answer:
The historical description enhances a reader's understanding of the personal narrative by highlighting how people used every part of the bison for their survival.
Step-by-step explanation:
The historical description enhances a reader's understanding of the personal narrative by reinforcing the idea that people were resourceful with bison by giving an example of how they used the dung. In this case, the dung served as fuel for cooking fires when dried in the sun. This example provides a concrete and specific detail that helps readers visualize how people made use of every part of the bison for their survival.
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