Si el universo está lleno de extraterrestres... ¿dónde está todo el mundo?: Setenta y cinco soluciones a la paradoja de Fermi y el problema de la vida extraterrestre

Excerpt from Historical Geography of Bible Lands: A Manual for Teachers The subject-matter of the course is weighty enough for adult students, while the method is sufficiently simple and vivid for pupils of fourteen years of age. The thirteen chapters provide a three-months' course of thirteen lessons. The course thus meets the requirements of a summer session of a Sunday school. If a more thorough study of the material provided. By the manual is desired, a course of several months' duration may be arranged by subdividing the chapters and devoting two or more lessons to each of them. This...

Eighty-eight lavishly illustrated pages of stepby-step coloured drawings and photographs teaches you how to grow orchids confidently, successfully and professionally. Written for the amateur and the professional without access to sophisticated laboratory equipment and chemicals, this contains all you need to know to become an expert.

The Inter-American Development Bank (IDB), in cooperation with the International Water Association (IWA), has developed a rating system that assesses the performance of water and sanitation service providers in a comprehensive way. AquaRating: Un estándar internacional para evaluar los servicios de agua y saneamiento aims to provide an industry standard for utilities. The innovative rating system seeks the improvement of the service delivered by means of a rigorous and systematic assessment. AquaRating comprises more than 100 assessment elements organized in eight rating areas: Service...

L'actual sistema energètic està basat en uns recursos no renovables, els combustibles fòssils, i el seu ús porta aparellada una sèrie de problemas, com l'augment de la concentració de diòxid de carboni en l'atmosfera. En aquest llibre s'analitza i s'explica quina serà la naturalesa d'un nou sistema energètic sostenible basat en fonts renovables. L'element central d'aquesta font d'energia del futur és l'hidrogen, que substituirà els combustibles derivats del petroli, enmmagatzemarà l'energia obtinguda de les fonts renovables intermitents i podrà convertir-se en electricitat en una ...