Cómo podemos utilizar el tornillo?

Defines levers, explains their functions, and suggests simple experiments to demonstrate how they work.

The Uses Of Wind Energy Is The Topic Of This Book. Explains The Positive And Negative Impact This Form Of Energy Can Have On Our World.

Follows the life and career of the French scientist who proved the existence of germs and their connection with diseases.

Ice cream is a solid. But when it melts, it becomes a liquid. Solids can change to liquids and back again by melting and freezing. Read this Spanish-translated book to learn what happens when heat and cold and solids meet.

This guide gathers a selection of more than 500 species of vertebrate animals cataloged and arranged in colored illustration. It is an exhaustive and complete guide that provides precise information about each species, and that captures all the beauty and diversity of the vertebrate world in spectacular design and with enthralling visuals.

Three Puerto Rican stories include the title story, which represents the land's indigenous Tainos; the tale of la Guinea, which is rooted in the nation's African culture; and la Mula's tale, a story of Spanish origin.

Color, brillo, mística y a la vez sentimiento de raza y profundidad impenetrable. Darío, creador del Modernismo, no sólo renovó el idioma y las estructuras, sino que aportó una estética más universal. (Esta edición es Premio Banco del Libro de Venezuela 1990).