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What surrounds the individual muscle cell?

Muscle cells have three coverings. The endomysium covers each individual muscle cell. The perimysium is a connective tissue sheath that covers small bundles of muscle cells known as fascicles. The fascicles make up larger muscle bundles that are then covered by a connective tissue sheath known as the perimysium. Connective tissue is innervated by the nervous system; therefore, each muscle covering allows for smooth contraction and relaxation by propagating action potentials throughout large muscle systems.

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How long can humans hold their breath underwater?

The women's record, as of 2014, was set in 2009 by Brazilian Karoline Meyer, who held her breath for 18 minutes and 32.59 seconds. These world records were set in cases where the person hyperventilated, or took in oxygen prior to submerging to clear out carbon dioxide. The world record for holding breath without the aid of oxygen is 11 minutes and 35 seconds, as of 2014.

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What does KSI measure?

KSI is almost exclusively used in the fields of engineering and architecture to measure large amounts of stress on materials; it may also be used to represent tensile strength. In all cases, KSI refers to pressure from tangible, physical objects. Engineers will sometimes use KSI in place of "pounds per square inch" when communicating with engineers in other parts of the world, as it does not require converting between the metric and imperial systems.

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Is water an inorganic compound?

Water would have to contain at least one carbon atom to be considered organic. Many inorganic substances are essential to life. Although it is essential for an organic compound to contain a carbon atom, many compounds are considered inorganic even though carbon atoms are present. The difference between organic and inorganic can be difficult to classify, although carbonates, allotropes of carbon, simple oxides of carbon and cyanides are all considered inorganic by Biology Online's dictionary.

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Is a soft drink a homogeneous mixture?

Examples of homogeneous mixtures include air, vinegar and dish soap. In a homogeneous mixture, the components are not individually visible and are typically not separable by mechanical methods. All components are in the same state of matter.\nHowever, a soft drink with ice is a heterogeneous mixture. The ice and liquid are not distributed evenly throughout the glass. Two samples of the drink may contain different components. In addition, two phases of matter are part of the mixture: solid and liquid.

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How long has sedimentary rock been around?

Researchers from the University of Chicago and the University of Colorado state that these rocks probably precipitated from seawater under oxygen-starved conditions and that the iron came from hydrothermal vents along mid-ocean ridges. Banded iron formations are not being formed in modern times because seawater now contains a much higher proportion of dissolved oxygen that would cause iron to precipitate rapidly near the vents.

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What was the strongest tornado on record?

A June 2013 USA Today article states that an EF5 tornado that hit near Oklahoma City on May 31, 2013 had winds of up to 295 miles per hour. This tornado, which hit El Reno, Okla., was the largest and widest tornado ever recorded with a width of 2.6 miles and the second strongest by wind speed. According to Dr. Jeff Masters at Weather Underground, the only tornado that had higher wind speed was a tornado that hit Moore, Okla., with wind speeds of up to 302 miles per hour. This tornado struck on May 3, 1999.

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Where can you find an online chart to convert Celsius to Fahrenheit temperatures?

Knowing such conversion formulas is useful, however. The formula for converting from Celsius to Fahrenheit is F = C * 9/5 + 32, where F equals Fahrenheit, and C equals Celsius, explains AskNumbers.com.\nThe Celsius scale places the boiling point of water at 100 degrees and the freezing point at zero degrees. This is a simplification over the more complicated Fahrenheit measurements. A temperature of zero degrees Celsius equals 32 degrees Fahrenheit.

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What are examples of solid mixtures?

Concrete is a mixture of lime, water, cement, sand and rocks. When these components are mixed together, the cement solidifies, forming a solid mixture. Although the hardening of the cement can be considered a chemical reaction, the actual mixture is held together by a physical force, and these components are still not chemically bonded.\nAlloys are also considered as mixtures. Alloys are homogeneous mixtures of two or more kinds of metal. Brass is a mixture of 70 percent copper and 30 percent zinc. Bronze is 90 percent copper and 10 percent tin. Alloying metals is like dissolving one metal int..

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What is the formula for potassium bromide?

Potassium bromide is a salt formed by the reaction of potassium with bromine:\n2K (s) + Br2 (g) ? 2KBr (s). It can also be obtained by reacting hydrobromic acid with potassium hydroxide: KOH (aq) + HBr (aq) ? KBr (aq) + H2O (l). Potassium bromide has a molecular mass of 119.002 grams per mole and its density is 2.74 grams per centimeter cubed. It has a high melting point of 1,353 degrees Fahrenheit.

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