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Why do people float in water?

When an object is placed into water, it is entering a cylinder of water from the surface to the bottom. It displaces some of the water in that cylinder, and the water beneath it exerts upward pressure. If the volume of water that is displaced is lighter than the object, the pressure will be insufficient to keep it afloat. If the equivalent volume of water is heavier than the object, the remaining water in the cylinder will keep it at or near the surface.\nHuman bodies tend to float due to stores of fat and to the volume of air stored in the lungs. However, those with very low body fat percenta..

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What is the melting point of metals?

When metals are heated, the temperature rises continually until the metal reaches the melting point. At that point the rise in temperature stops until all the solid converts into a liquid. The energy that is applied to the system at the melting point causes the phase change. The melting point is unique for each different metal and is useful for scientists attempting to identify an unknown sample of the material. In addition, each metal requires a different amount of energy for the phase change, which scientists call the latent heat of fusion.\nIron has a melting point of 1536 degrees Celsius w..

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What is the basic structure of a human cell?

The human body is made up of roughly 10 trillion cells, each held together by a cell membrane. The cell membrane is semi-permeable, with various protein molecules allowing substances in and out of the cell. It completely surrounds the cell, protecting all the organelles inside. The cytoplasm is the jelly-like substance inside that keeps the organelles in place.\nThe nuclear membrane separates the nucleus from the rest of the cell. It has nuclear pores that allow nutrients into the nucleus and carry waste out. The nucleolus governs the cell organelles, such as the lysosomes that help absorb nut..

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What are examples of animals in the class Aves?

Aves is a class in the subphylum Vertebrata, phylum Chordata and the kingdom Animalia. Organisms in this class all share the same characteristics:Skin covered in feathersWarm-bloodedLay hard-shelled, waterproof eggsNo teeth, but rather a bill or a beakOnly walk on two legsWingsMost members of this class can flyThere are 29 orders, or sub-groups, of this class, which includes more than 10,000 known species. Some of the more common examples include:Anseriformes - ducks, swans and geeseFalconiformes - falcons, eagles and hawksGalliforomes - fowl such as chickens, turkeys and pheasantStruthionifor..

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What is the boiling point of oil?

Olive oil reaches a boiling point at 375 F. At the higher end of the spectrum, safflower oil boils at 510 F. The boiling point of the different elements that comprise crude oil range from 34 F (liquefied petroleum gas) to more than 750 F (refinery gas oil).

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Are there regular UFO sightings across the world?

Reports of UFO sightings have increased steadily since the first recorded sighting in 214 BCE. Sightings were reported more regularly from the beginning of the 20th century until, by the 1940s, the rate of reporting had increased to an average of one per year.\nRecords of sightings have been maintained in seven countries. The United States has reported a high number of sightings since the first well-known UFO sighting occurred in 1947. In the summer of 1952, the number of UFO reports had climbed to such a level that the Central Intelligence Agency prompted the U.S. government to establish a pa..

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Are GMOs safe for all age groups?

GMOs are a very recent addition to people's diets, so it is possible that later studies may reveal health concerns linked with their consumption. There are some anti-GMO organizations that make claims that some studies have already revealed risks in consuming genetically modified foods, but these studies are heavily flawed. One such commonly cited study claims that genetically modified corn causes tumors in rats, but a closer examination of the study reveals that the experimenter failed to perform statistical analyses or use enough rats, according to the Genetic Literacy Project.

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How can you find out when rocket launches occur at Cape Canaveral?

Located on Merritt Island, Florida, the Kennedy Space Center has been NASA's primary launch center since December 1968. Major launches for the Apollo, Skylab and Space Shuttle programs have all taken place at the Kennedy Space Center. The site itself is a major tourist attraction, and the Kennedy Space Center Visitor Complex offers public tours of both the center and the Cape Canaveral Air Force Station.

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Where is xenon found in nature?

Sir William Ramsay and M.W. Travers discovered xenon in 1898. Its name comes from the Greek “xenos,” which means "strange." It is also a very heavy gas. Its chemical symbol is Xe, and it has an atomic number of 54. There are nine stable isotopes of this inert gas.\nThe method used to produce this gas commercially extracts it from liquid air. Its applications include bubble chambers, electron tubes and strong lamps that kill bacteria.

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What is vascular shunting?

Modern shunts are intended to treat vascular disease rather than injury, according to TechLink. However, the U.S. Air Force has created a vascular injury shunt intended to treat trauma injuries.\nWhile further studies are needed to gauge its true effectiveness in cases of injury, its use is stated to not cause worse outcomes for the individual, according to the 'Journal of Vascular Surgery.'

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