A 52-card deck has about 8×10^67 possible orders, far more than all shuffles in history, so a properly randomized order has almost certainly never occurred before.
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A mirror reverses only front and back, along the axis perpendicular to its surface. The left-right flip comes from how we imagine turning ourselves around, and specialists still frame the puzzle in different ways.
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Yes, by most estimates. Shannon's figure of about 10^120 possible games far exceeds the roughly 10^80 atoms, though the number of positions is much smaller.
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A coastline has detail at every scale, so its measured length grows as the ruler shrinks. Britain's coast therefore has no single well-defined length, only lengths tied to a chosen scale.
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The Sun is so far away that a mountain's height changes nothing. Thinner air at altitude holds less heat and expands and cools, so temperature falls as you climb.
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A returning boomerang is a spinning wing. Its blades make uneven lift, and gyroscopic precession turns that uneven lift into a curved path back to the thrower.
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It depends on what counts as a shark. Shark-like fishes date to about 400 million years ago, before the first trees, but modern sharks emerged about 195 million years ago, after them.
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Venus is hotter because its dense carbon dioxide atmosphere traps heat in a runaway greenhouse effect, while airless Mercury loses heat to space.
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Bananas are slightly radioactive because of potassium-40. One banana gives roughly 0.1 microsieverts, an informal unit called the banana equivalent dose, which poses no meaningful risk.
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Yes. Stegosaurus lived roughly 80 million years before T. rex, while T. rex lived about 66 to 70 million years before the present, so we are nearer to T. rex.
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Yes, by current estimates. About 3 trillion trees outnumber the Milky Way's roughly 100 to 400 billion stars, though both figures are estimates.
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Some experiments report hot water freezing first, but results are hard to repeat and researchers disagree over whether the Mpemba effect is real or an artifact of measurement.
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Yes. Cleopatra lived roughly 2,500 years after the Great Pyramid was built and about 2,000 years before Apollo 11, so the Moon landing is nearer in time.
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Yes. Teaching existed at Oxford by 1096, while Tenochtitlán was founded in 1325 and the Aztec imperial alliance formed in 1428, so Oxford is older by centuries under either dating.
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Venus spins once in about 243 Earth days but orbits the Sun in about 225, so its rotation outlasts its year. Why it spins so slowly and backward is not fully settled.
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Film records still frames at fixed intervals. If a wheel turns most of the way to the next spoke between frames, the nearest match looks like backward motion.
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We feel changes in motion, not steady motion. Earth's spin is smooth, we and the air move with it, and gravity far outweighs the tiny outward effect of rotation.
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It is an illusion: the Moon's size does not change. Scientists agree that perceived distance plays a part, but no single explanation has convinced everyone.
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Rivers carry small amounts of dissolved salts that the ocean collects, while evaporation leaves the salt behind and rain keeps rivers diluted. Vents and volcanoes add more.
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Honey has very little available water, is acidic, and contains some hydrogen peroxide, so microbes cannot grow in it. It stays stable as long as it is sealed and kept dry.
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The main reason is safety: a round cover cannot fall through its own opening. Easier rolling, easier placement and simpler manufacture are secondary reasons.
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In 2006 the IAU defined 'planet' to require clearing the orbital neighbourhood. Pluto meets the other criteria but not that one, so it became a dwarf planet.
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The Dead Sea has no outlet, so water leaves only by evaporation and salt stays behind. The resulting dense water pushes up on swimmers, so floating takes almost no effort.
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Yes. Reno sits at about 119.85° West and Los Angeles at about 118.41° West, so Reno is farther west by roughly 1.4 degrees of longitude.
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The Aleutian Islands cross the 180th meridian, so some Alaskan land lies at eastern longitude. By longitude Alaska holds both extremes; by map position Maine is easternmost.
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Earth bulges at the equator because it spins. Chimborazo sits almost on the equator, so its summit is about 2.1 km farther from the center than Everest's, though Everest is higher above sea level.
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A rolling bicycle stays up because its steering turns into any lean. A rider usually supplies this, but several bike features can do it alone.
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The arithmetic holds: 42 doublings of a 0.1 mm sheet give about 440,000 km, past the Moon. But the fold cannot be done, and a geometric argument says the sheet itself would need to be enormous.
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Light moves at full speed, but dense solar plasma scatters it constantly in random directions. The resulting zig-zag makes the trip very long, with estimates ranging from tens of thousands to millions of years.
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Yes. Alexander Bain patented the core idea of the fax in 1843, about 33 years before Bell's telephone patent, though it was not yet practical for everyday use.
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The claim is a loose way of saying many human genes have distant counterparts in bananas. Estimates run from about 25% to 60% depending on method, and shared DNA is far lower, around 1%.
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The old 10:1 ratio is wrong. Current estimates put bacteria and human cells at roughly 1:1, with bacteria slightly ahead in a typical adult man, and the exact result depends on definitions.
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