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International currencies, money, various banknotes, currency

A Brief (and Fascinating) History of Money

African Americans demonstrating for voting rights in front of the White House as police and others watch, March 12, 1965. One sign reads, "We demand the right to vote everywhere." Voting Rights Act, civil rights.

Timeline of the American Civil Rights Movement

Dr. Martin Luther King Jr. addresses marchers during his "I Have a Dream" speech at the Lincoln Memorial in Washington. August 28th 1963

Was Martin Luther King, Jr., a Republican or a Democrat?

Apollo 12 astronaut Charles "Pete" Conrad stands beside the U.S. flag after is was unfurled on the lunar surface during the first extravehicular activity (EVA-1) Nov. 19, 1969. Footprints made by the crew can be seen in the photograph.

How Many People Have Been to the Moon?

The Lost Colony of Roanoke, North Carolina, where 115 people mysteriously disappeared c. 1590. John White discovers the word Croatoan carved onto a tree upon his return to the deserted Roanoke Colony in 1590

The Lost Colony of Roanoke

Panoramic view at sunrise of moai, Ahu Tongariki, Easter Island (Rapa Nui), Chile

6 Lost Civilizations

Demystified - Do Lemmings Really Commit Mass Suicide? illustration

Do Lemmings Really Commit Mass Suicide?

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connectedness countable set universal set null set disjoint sets cardinal number hierarchy of sets basis element subset foundations of mathematics probability and statistics numerals and numeral systems matrix function fractal graph derivative algorithm vector

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