In this episode, we're answering a question from listener Katelynn: "Why is car exhaust bad for the planet?" Our planet NEEDS some carbon dioxide, but cars are pumping more into the atmosphere than our carbon cycle can handle. We'll explore what all this carbon means for our planet. And we talk to Anne Co, a scientist who is working to change how we fuel our cars, so we can cut back on all this carbon dioxide. She explains how fuel cells and batteries work to power electric cars. Anne's vision for the future of cars can be summed up in one word: electric.