Un día de trabajo de un astrónomo (A Day at Work with an Astronomer)

In this stimulating, Spanish-translated nonfiction book, readers will discover the various types of friction--including rolling friction, sliding friction, fluid friction, and static friction--and the huge impact it has on nature, machines, and our lives. In addition, readers are encouraged to perform basic experiments to assist in the understanding of friction, kinetic energy, and water resistance. With real-life examples, colorful images, accommodating graphs and charts, and informational text, this title will inspire and engage children.

Deforestation, hunting and global warming have endangered countless species. The orangutan, okapi, giant panda and the blue whale are just some of the 30 species on the brink of extinction that are featured in this book. They need your help. The International Conservation Society illustrates how many of these species are left in the wild, and the latest status regarding their natural environment. You'll learn how you can aid endangered species and help sustain the ecosystems that give them life.

Perfect for readers interested in learning more about other faiths, this unique collection offers an in-depth look at the major religions of the world. Rich with fascinating facts, each edition includes illustrations, photographs, glossaries, and information on the history, customs, and doctrines of each religion. By offering readers a deeper understanding of the beliefs of others, this collection encourages tolerance and respect in an increasingly multicultural world. Perfecto para lectores interesados en aprender más sobre otras religiones, esta colección única ofrece un análisis...

El libro pretende contar un poco de la década de los cuarenta, como Trece Rosas y el fusilamiento de Quiñones entre otros hechos y siempre bajo la atracción del torbellino europeo y de lo peligro de invasión por parte de Hitler o de los Aliados y la victoria de Franco en La Guerra Civil.