Marne Ventura 
Tornadoes 

A tornado, or twister, is a tube of rotating wind. About 1, 000 twisters touch down in the United States each year. Find out more in Tornadoes, one of the titles in the Surviving series. Surviving 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, hands-on experiments, and much more.