Continentes de la Tierra (Earth’s Continents)

Diamonds and salt are both minerals, but diamonds are more rare than salt. Curious readers will learn what physical and chemical conditions must be present for minerals to form. They'll discover how minerals are identified and how they are used in daily life. Informative and interesting text presents readers with this science content in a fun way. A graphic organizer shows how different minerals are identified and fact boxes provide readers with exciting supplementary information.

Técnico electricista 8 - Curso visual y práctico Generación y transmisión de energía En esta clase revisaremos los tipos de generación, analizaremos sus valores característicos, y conoceremos las centrales de generación y sus componentes. Explicaremos la necesidad de contar con líneas de transmisión de alta tensión y los tipos de estaciones transformadoras, las torres de alta tensión y los aisladores. También veremos las características de la distribución de la energía eléctrica y describiremos los componentes que intervienen en este proceso.

In 1991, preparation for the construction of a new federal office building led to a startling discovery: a skeleton. Further excavation exposed the bones of 420 men, women, and children. This area of New York had been a burial ground set aside for both free and enslaved Africans during the 1600s and 1700s. It’s thought to be one of the most important archaeological discoveries of the 20th century. This noteworthy book—which includes sidebars, fact boxes, a timeline, and maps—fills in the gaps of history books, exposing much about what life was like in colonial New York for Africans.

Description Packed with action and full of the vehicles kids love most, Big Movers is tons of fun! Young readers are there as a front loader scoops piles of gravel for a new roadway, a wrecking ball demolishes and old building, and more. A chunky, movable piece on each vehicle makes reading this book an interactive adventure.