Lisa Greathouse 
busqueda de la velocidad [PDF ebook] 
Los vehiculos

The need for speed is the motivating factor in this engaging, Spanish book. Readers learn the history of travel from the very slow to the supersonic and beyond, including everything in between. They learn and discover the factors that influence motion for all types of vehicles: land, air, and water alike. They also learn different ways to measure speed and read about energy uses for different vehicles. With greater speed comes greater risk. Readers learn how engineers are always seeking new and better ways to keep people safe as they travel faster and go farther.