Vietnam Veterans Memorial Infographic (History Channel)

How are the names arranged on the Vietnam War Memorial?
The earliest date recorded on the memorial was:
The last date recorded on the wall was:
How many names are currently on the wall?
How many women are listed on the wall?
Who designed the memorial?
How many sets of brothers are listed?
How many father and sons are listed?
What is the legal age of enlistment? Is it possible for a 17 year-old to enlist?