Why is seawater salty? What causes volcanoes to erupt? Why don't man-made satellites fall from the sky? What makes people sleepy? Answers to these questions an…
Why is seawater salty? What causes volcanoes to erupt? Why don't man-made satellites fall from the sky? What makes people sleepy? Answers to these questions and more are in this animated title which explores topics of nature, customs, and technology.
