There are more than 1,500 active volcanoes around the world. Most of Earth's active volcanoes are found in a region called the Ring of Fire. Discover more about this feature of the natural world in Volcanoes, a title in the Focus on Earth Science series. Focus on Earth Science is a series of AV2 media enhanced books. A unique book code printed on page 2 unlocks multimedia content. These books come alive with video, audio, weblinks, slideshows, activities,...