El ciclo del nitrógeno (The Nitrogen Cycle)

Reptiles y anfibios is one book in the Spanish-language Gran Atlas de la Ciencia series that covers today's most popular science topics, from digital TV to microchips to touchscreens and beyond. Perennial subjects in earth science, life science, and physical science are all explored in detail. Amazing graphics--more than 1,000 per title--combined with concise summaries help students understand complex subjects. Correlated to the science curriculum in grades 5-9, each title also contains a glossary with full definitions for vocabulary.

When rocks change because of environmental conditions, the new rocks are called metamorphic rocks. A rock's chemical or physical makeup may change because of conditions such as temperature, stress, or pressure. Your readers will learn fascinating facts including where metamorphic rocks are most commonly found, the different types of metamorphism, and how metamorphic rocks are identified. Full-color photographs depict these rocks in nature. A helpful graphic organizer shows how these fascinating rocks form.

Nueva traducción, acompañada de un completo estudio introductorio y un amplio cuerpo de notas, de esta obra de madurez en la que Cicerón analiza cuestiones de ética filosófica que, a juicio de su autor, pueden ayudar al lector a hacer más llevadera la tempestuosa travesía de la vida.

Provides encouragement and advice for facing life's challenges, just for girls, with blank spaces to fill in goals and accomplishments.