Read this excerpt from the introduction to wheels of change by sue macy.

wheels of change looks at how the bicycle took america by storm in the 1880s and '90s, and especially at the ways in which it changed women's lives. it also explores the bicycle culture of the era with short features, appearing after each chapter, that highlight the impact of the two-wheeler on everyday life. you'll meet celebrity cyclists of the day, learn cycling slang, read about cycling songs and magazines, and see bicycles used in advertisements for everything from carpets to candy to baking flour.

what is the author’s purpose for including this in the introduction?

to explain the historical significance of bicycles in america
to outline the key points that are presented in wheels of change
to inform the reader about how bicycles changed women’s lives
to emphasize the personal significance of bicycles in her life