아빠는 공부쟁이

03:25 Although global attention is focused on the pandemic, cities are still sinking and sea levels are still rising. And high-tech solutions are definitely going to help us solve some of these problems, but in our rush towards the future, we tend to forget about the past. 03:43 In other parts of the world, where rivers are contaminated with sewage, a city of 15 million people cleans its waste w..