I think that the ship that German submarine sunk was the Lusitania ship
The CCC addressed the problem of unemployment and offered jobs to young men. The WPA encouraged people to volunteer and encourage public works.
Answer:
There are many people who could exemplify the period, but a particularly important figure is Martin Luther King.
Martin Luther King is the central figurehead of the Civil Rights Movement, which was perhaps the most important social movement in American during this time. Martin Luther King was a great leader who gave a voice to the needs of African Americans, who had been subjected to all kinds of abuses from centuries before.
He gave a message of change, but always in peaceful manners. He was not a provocator, and openly called for tolerance between all people, regardless of the color of skin, or other attributes.
This is why he became such a central figure of this period.