America's Got Talent The top 10 acts compete for the last time in the final round of the competition. 8 p.m. NBC
The Vietnam War In “The River Styx (January 1964-December 1965),” part three of the Ken Burns-Lynn Novick documentary series, Hanoi ramps up the conflict by sending troops to South Vietnam, which is already in disarray. 8 and 10 p.m. KOCE and KPBS
The State Marriage to a foreign fighter is challenging, but Ushna is determined to make it work, while Shakira suffers brutal consequences for turning down a proposal, 9 p.m. National Geographic. The series finale follows at 10.