In what way did the Paris Peace Accords fail?

Most US troops did not withdraw.
Prisoners of war were not released.
The negotiated ceasefire did not last.
North and South Vietnam were never unified.

What makes fort sill historically unique among other regional military installations? a. it is the site where seven major commanders of us military efforts were trained. b. it houses the largest explosive weapons factory in the united states. c. it specializes in training soldiers to preserve the cultural artifacts of nations invaded by the us military. d. it is the oldest functioning installation in oklahoma.