In paragraph form, briefly explain what the purpose of a timeline is

The purpose of a timeline is to show a series of actions within a certain period of time in a chronological order, that can help someone to better understand the change, recurring events, causes and effects, and key events of historical, social, and scientific importance.

Sorry if this does not make sense, I used translate because English is still difficult and sometimes confusing for me.

racism and segregation.

affirmative action refers to the policies that take gender, race, or ethnicity into account in order to promote equal opportunity.

employers subject to title vii are prohibited from taking race or sex into account in any employment decisions. aa is a penalty for having any job group substantially statistically "underutilized" in any race or either sex. the employer must take steps to eliminate the underutilization, then stop, ending its aa efforts