Energía del viento

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

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

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

Enamorado de la vida y de las causas de los oprimidos, Neruda, poeta del amor y la libertad (premio Nobel de Literatura 1971), representa y sintetiza todo el vigor y contradicciones de un mundo a la vez muy reciente y antiguo: América del Sur.

Design a flexible protective layer for a space suit. Space suits have come a long way. The look and function of space suits has evolved over time, but their purpose has always been the same--to keep astronauts safe. From the first suits worn during the Mercury missions, to the latest suits being tested by NASA, there have been great improvements. Learn all about the science behind space suits and how they have changed over time. Created in collaboration with the Smithsonian Institution, this Spanish Smithsonian Informational Text builds reading skills while engaging students' curiosity about...

El carácter de Kolmogórov se forjó en una época de revoluciones sociales y guerras mundiales. Vivió el estalinismo, la posterior rectificación de errores y el inmovilismo que luego daría paso a la perestroika. Aunque siempre se consideró a sí mismo un matemático puro, una parte esencial de su obra fueron sus investigaciones aplicadas a otras ciencias. Sus esfuerzos estaban regidos por una idea clara - discernir las diferencias y similitudes entre orden y caos. Mucho más que cualquier otro matemático, amplió los dominios y la comprensión humana del azar. Reinó en una escuela...

In 1862, the American Civil War was underway, actively tearing the United States apart. At the start of the war, President Abraham Lincoln's main goal was preserving the Union, but he was now ready to make a stand on slavery. The Emancipation Proclamation was one of the most important documents of its time, but its contents can be confusing. This volume gives readers context for the proclamation, as well as explains what it says and its results, in uncomplicated language appropriate for those reading below level and those looking for a review of this subject.