> So imagine 150 years of gasoline usage help lead the world to be green and change to an energy source for "4 billion years." I'm interpreting this sentence a

> So imagine 150 years of gasoline usage help lead the world to be green and change to an energy source for "4 billion years." I'm interpreting this sentence as meaning "think about how we've far we've come in 150 years: from inventing gasoline, to being in a position to consider an environmentally sustainable energy source on the time scale of 4 billion years".