How Do We Know a Tornado's Wind Speed?00:44
NBC Meteorologist Bill Karins explains how a tornado's wind speed is determined.
Who is Third Party Candidate Jill Stein?00:37
What’s the Youngest Age to Compete in the Olympics?00:36
What a Heat Dome?00:36
Is China Militarizing in the South China Sea?00:37
How Do You Become a Member of the Academy?00:37
Wall Street Lingo: What's a Corporate Inversion?00:36