The 3 groups are;
1.) African American
2.) Youths
3.) Women
Why and how they were added;
1.) African American: In the year 1870, the 15th amendment granted them the right to vote. They were not allowed to vote previously because a literary test was used to test them before they could vote
2.) Youths: in the year 1970, the voting rights act allowed youths (18 year olds) to vote.
3.) Women: The 19th amendment allowed women to vote.
Hardship faced:
African American: Discrimination and racism
Youth: they were sent to war
Women: It was the way things were. It was the status quo.