"After teaching for many years, one job posting changed the arc of her life." What impact does the word arc have on the overall tone of the the text?

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Katherine Johnson reached for the stars long before she helped send humans into space.

Born on August 26, 1918 in West Virginia, Johnson had a gift for numbers. As Johnson later described, she spent her life counting—counting the steps she walked, the dishes she washed. "Anything that could be counted, I did," she once said.

School came easily for Johnson, and she completed eighth grade by the age of 10. After that, she couldn't continue learning locally because her county didn't provide a secondary education to African American students. Johnson's father Joshua moved the family 120 miles away so she could attend high school. By 18, she graduated with honors from West Virginia State College, receiving degrees in mathematics and French. She then went on to teach these subjects at a public school.

After teaching for many years, one job posting changed the arc of her life. The National Advisory Committee for Aeronautics (NACA) was looking to hire women to fill unique positions. The job title: Computer.

The word "arc" shows that Katherine's life has ended a stage to start a much larger one.

Explanation:

The impact of the word "arc" in the text, presents the impact of completion and restart, showing that Katherine's life has completely changed, finishing one stage to the beginning of another stage much bigger and more important in her professional life, something that even changed her personal life and the way she showed herself to the world. This shows that she achieved professional success, despite having limitations related to racism and intolerance.

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