Sometimes you are lucky enough to meet someone who totally changes your life. That happened to me. The person I met was Bill Gates Sr. It was 1998.

Bill Gates, billionaire and father of three, ... "Thank you @columbiapublichealth for this incredible educational opportunity and the village around me who made this possible.

Bill Gates: What they do is they stick CO2 in here in the cement, and they mix them up. And so, you're able to actually get rid of some CO2 by sticking it in the cement. Right now they get rid of ...