Description
Look at a map of the world or a globe and explore the question, how many oceans do we have on Earth, from a critical perspective.
2. Can you think of examples of mutualism among humans and other animals?
3. Why do you think that oceanic crust (rocks formed at the bottom of the oceans) is heavier than continental crust (rocks formed on land or underground)?
4. Why is it difficult for scientists to agree on the definition of an active volcano?