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Why are light bulbs filled with argon gas?

Argon is also used to create an inert atmosphere for growing semiconductor crystals, arc welding and for processes that need protection from other kinds of atmospheric gases. Argon was originally discovered in 1894 by an English chemist named Lord Rayleigh and a Scottish chemist named Sir William Ramsay. Argon is a nonmetal gas at room temperature and is assigned the number 18 on the period table of elements.

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How does culture age affect the results of a gram stain?

Gram stains reveal the structural differences in the cell walls of organisms in the laboratory. Gram-positive organisms have a thick cell wall containing up to 90 percent peptidoglycan and appear blue or purple under the microscope after staining with crystal violet. Gram-negative organisms have a much thinner cell wall containing up to 10 percent peptidoglycan and a high lipid content. These organisms appear red or pink under the microscope after staining with crystal violet.\nThe gram stain is a critical laboratory test that is integral to the study and treatment of infectious disease. Many ..

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Which states have the lowest and highest average gas prices?

One factor that creates variation in fuel prices from state to state is taxes. In some states, taxes account for 15 percent or more of the price per gallon. In Pennsylvania, for example, 21 percent of the gas price goes to the state. In eight states, gasoline taxes make up less than 10 percent of the retail price. In addition, not every state calculates their tax in the same manner. In some states the tax is a flat fee. In other states the fuel tax is linked to the price of gasoline, so as gas prices fall, revenues fall.\nThe market forces of supply and demand also affect gas prices. The South..

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What eats a tiger?

The tiger is an apex predator that is located at the center of the food web in its environment. While large animals like bears, elephants and buffaloes do not hunt or eat tigers, they can still pose a physical threat when challenged. The biggest threat to tigers are humans. Humans trap, poison and hunt tigers for sport and for their skins, as well as for trophies and to make some medical remedies used in Asian medicine. The whiskers of the tiger, for example, are considered to be a powerful aphrodisiac and also part of a dreadful poison, depending largely on regional beliefs.

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What are the different types of force?

An applied force is the force exerted on an object with the intent to move it. Frictional force is the force that opposes motion. Static friction acts on objects at rest and prevents them from moving. Kinetic friction acts on objects in motion and works in a direction opposite to the motion. Air resistance is a kind of friction exerted by air on moving objects.\nNormal force is exerted on an object by the surface it is resting on to support its weight. Spring force is exerted by either a compressed or stretched spring. Tension force is the force acting on a rope or a string that is pulled tigh..

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What is pseudomonas?

Infections acquired by people who are already hospitalized for an illness or condition that weakens their immune systems are called nosocomial infections. Pseudomonas bacteria are among the most common pathogens responsible for this type of infection, spread by healthcare workers or on medical equipment or other hospital surfaces. Many cases of pneumonia occur in hospitals because of pseudomonas infections acquired through breathing machines, according to WebMD.\nPseudomonas bacteria also spread in hospitals through intravenous needles and catheters. Patients hospitalized for burns and punctur..

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What animal has the largest eyes in the world?

The giant squid's enormous eyes help it see in the darkness of the deep sea. These elusive creatures have been talked about for centuries, but scientists know very little about them because their isolated underwater habitats make them hard to research. In addition to its large eyes, the giant squid also has a tough, sharp beak that helps it kill and eat its prey.

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What is the process used for harvesting adult stem cells?

Harvesting adult stem cells is a relatively complex procedure, but it holds great benefits for potential medical purposes. As Sciencedaily.com explains, adult stem cells are much less controversial when it comes to research purposes in comparison to embryonic stem cells. Adult stem cells have already been used successfully to treat leukemia and other cancers of the blood.

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What are the similarities between the frog and human muscular systems?

Almost all major human muscle groups, including the pectorals, deltoids, quadriceps and abdominal muscles are present in frogs and recognizably similar in structure to those of humans. While the form of the muscles is different due to the anatomical differences between the species, common features such as the division of the quadriceps muscles into the rectus femoris, vastus lateralis and vastus medialis are apparent. These similarities are less apparent in the smaller muscles of the feet of the frog, where the anatomy of humans and frogs is highly dissimilar.\nFrogs and humans also both have ..

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How long does it take Saturn to rotate on its axis?

Scientists do not believe that the planet has actually slowed its rotation. Instead, they think that Saturn's magnetic field and its location have more to do with the conflicting readings. Nevertheless, Saturn's day is less than half that of Earth's 23.934 hour-long day. By contrast, a year on Saturn, the second largest planet in the solar system, is slightly less than 30 years on Earth.

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