World facts, geography, history.
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Portuguese is Brazil's official language.
Brazil was colonized by Portugal.
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Angkor Wat is a vast temple complex in Cambodia.
It was originally built in the Khmer Empire.
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Alexander Fleming discovered penicillin's antibacterial effect in 1928.
The discovery led to the development of antibiotics.
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Ernest Hemingway wrote The Old Man and the Sea.
The novella follows an aging Cuban fisherman.
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Persian, also called Farsi, is Iran's principal official language.
It belongs to the Indo-Iranian language family.
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The Giza pyramid complex lies near Cairo, Egypt.
It includes the Great Pyramid and the Sphinx.
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George Washington served as the first U.S. president.
He held office from 1789 to 1797.
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Platelets gather at damaged blood vessels and help form clots.
This reduces blood loss after injury.
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Wind turbines convert the kinetic energy of moving air into electricity.
It is a renewable energy source.
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The American Civil War was fought from 1861 to 1865.
Its central issues included slavery and federal union.
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The kidneys filter the blood and regulate water and salts.
Their waste product is excreted as urine.
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Carbon dioxide is a major greenhouse gas released by fossil-fuel use.
It traps heat in Earth's climate system.
