Lobachevski

The United States grew rapidly from the time of the Louisiana Purchase to the building of the Transcontinental Railroad. All of this expansion came at the expense of Native American populations that had either lived in the region for centuries or been forced there from ancestral homes in the East. Tribes memorably fought on their own and together in an doomed effort to retain the land and a lifestyle that had long sustained their families. This book outlines some of the major conflicts of the Westward Expansion, and of the treaties and were signed, and often broken, by representatives of the...

Imagine traveling at half the speed of a jet plane without ever leaving the ground! Students will discover the technology that makes such speeds possible, from special tracks and safety precautions to aerodynamically designed trains. What are the limits to the speed of trains? What imposes those limits? Students also will read about the future of passenger train travel, from flying trains to trains that use huge magnets to levitate inches or centimeters off the track. Some trains safely reach speeds of more than 200 mph!

En 1995, Iqbal Masih, se convirtió en mártir por la lucha contra la esclavitud infantil al ser asesinado en Lahore, su localidad natal. Iqbal denunció su situación ante la opinión pública para concienciar al mundo de una injusticia que afecta a millones de menores en el mundo. A partir de la recreación de los testimonios de los que lo conocieron, lo escucharon o lo odiaron, asistimos a la descripción de un personaje cuya labor ha sido imprescindible en la búsqueda de un mundo mejor.

Enciclopedia que descubre las curiosidades, costumbres y récords de los animales a través de espléndidas imágenes y rigurosos textos. ¿Quién es el animal más veloz?¿Cómo cazan los leones? Un libro que recoge, en definitiva, la lucha por la supervivencia en el mundo animal.