tracking
Now Playing:
via YouTube.
Now Playing:
via the Copy Cat Channel.
Now Playing:
via YouTube.
Now Playing:
via YouTube.
Now Playing:
via the New York Times.
Now Playing:
via the White House.
Now Playing:
via YouTube.
Now Playing:
via YouTube.
Now Playing:
via Joe Budden VEVO.
Now Playing:
via the Heritage Foundation.
Now Playing:
via YouTube.
Now Playing:
via YouTube.
Now Playing:
via YouTube.
Now Playing:
via YouTube.
Now Playing:
via YouTube.
Now Playing:
via the Associated Press.
Now Playing:
via Victoria's Secret.
Now Playing:
via Rachel Whitaker.
Now Playing:
via YouTube.
Now Playing:
via NYC Mayor's Office.
Now Playing:
via YouTube.
Now Playing:
via YouTube.
Now Playing:
via YouTube.
Now Playing:
via YouTube.
Now Playing:
via YouTube.
Now Playing:
via MTV.
Now Playing:
via COOLS.
Now Playing:
via KateyShawVEVO.
Now Playing:
via LivePublic
Now Playing:
via YouTube.
Now Playing:
via YouTube.
Now Playing:
via TIME.
Now Playing:
via YouTube.
Now Playing:
via YouTube.
Now Playing:
via YouTube.
Now Playing:
via The Aspen Institute.
Now Playing:
via YouTube.
Now Playing:
via YouTube.
Now Playing:
via Consolato USA Milano.
Now Playing:
via YouTube.
Now Playing:
via YouTube.
Now Playing:
via PBSNewshour.
Now Playing:
via NYC Mayor's Office.
Now Playing:
via the Associated Press.
Now Playing:
via YouTube.
Now Playing:
via Washington Free Beacon.
Now Playing:
via Washington Free Beacon.
Now Playing:
via Hunger in the Night.
Now Playing:
via Numberphile.
Now Playing:
via YouTube.
Now Playing:
via Associated Press.
Now Playing:
via Dr. Prodigious.
Now Playing:
via YouTube.