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blanket of gases surrounding Earth that contains about 78 percent nitrogen, 21 percent oxygen, and 1 percent other gases such as argon, carbon dioxide, and water vapor
study of materials that make up Earth and the processes that form and change these materials, and the history of the planet and its life-forms since its origin
all the water in Earth's oceans, lakes, seas, rivers, and glaciers plus all the water in the atmosphere
study of Earth's oceans including the creatures that inhabit its waters, its physical and chemical properties, and the effects of human activities
Le System International d'Unites (SI)
replacement for the metric system; based on a decimal system using the number 10 as the base unit; includes the meter: (m), second: (s), and kilogram: (kg)
a method used by scientists to express a number as a value between 1 and 10 multiplied by a power of 10
an idea, a system, or a mathematical expression that represents the idea being explained
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