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This video presents the different stages of coal formation.
A periodic climate pattern that occurs across the tropical Pacific Ocean every five years.
The surface of the Earth has been formed into its present state both by external and internal...
An earthquake is one of the most devastating natural phenomena.
The diameter of our galaxy is about 100,000 light years; it contains more than 100...
A glacier is a large body of ice that forms from snow, and is in constant, slow motion.
A Föld legbővizűbb folyama, az Amazonas és vízgyűjtő területének
A geyser is a spring characterized by intermittent discharge of water and steam.