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What is ultrasonic sound?

Hertz is a measure of frequency. A sound that arrives at its target with a frequency of one wave crest per second is vibrating at 1 hertz. The human ear can detect sound from about 20 to 20,000 hertz, above which is the ultrasonic range. Many animals, such as bats and dolphins, use ultrasonic frequencies for communication and echolocation, as very high-frequency sounds have a short wavelength and can be used to develop a high-resolution picture of the surrounding world.\nNoninvasive medical scans require a higher resolution than can be achieved at frequencies heard by animals, so scanners desi..

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Where in the armpit are lymph nodes located?

Lymph nodes in the anterior group are also called pectoral axillary nodes, and the posterior group is also referred to as subscapular. There are about 15 to 30 axillary lymph nodes.\nThe apical axillary nodes drain lymph from the other groups into the lymphatic ducts in the neck. Because of this function and their location near the chest, they may be involved in the spread of breast cancer into other areas of the body.

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How do animals obtain the nitrogen they need?

The atmosphere contains about 78 percent nitrogen, which is an element. This nitrogen is in an unusable form for plants or animals, however. Instead, animals and humans eat plants or eat other animals that eat plants. The plants are rich in nitrogen that they acquire from either the soil or the water in which they grew. When plants or organisms die, they return the nitrogen they contain to the soil or water. Thus, the nitrogen is available to fuel the cycle again.

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What is soil texture?

Sand has larger particles and feels gritty. This course-textured soil is comprised of sand particles between medium- and coarse-sized particles. Clayey or fine textured soil has clay particles that are also the smallest particles of the three types, and the physical properties of soil containing clay makes the soil gummy and sticky. Silt has moderate-sized particles and a smooth, flour-like texture. Loam soil consists of clay, silt and sand sized particles. Soil texture can also be identified by feel; clay is sticky, silt is smooth and sand is gritty.

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What is "dBZ" in weather?

Computer systems generate base reflectivity images at different angles of inclination. The images help detect the presence or possibility of precipitation, assess storm structure and determine atmospheric boundaries. If the radar receives back a strong signal, it yields a greater dBZ value, which implies a more intense precipitation. A reflectivity image may feature one of two color codes representing different dBZ values.

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What is Sulfur 8?

The main focus of the Sulfur 8 product line is to improve the health of the scalp and hair. The products also make the hairstyling process easier for the individual. The products add moisture to the scalp and are safe enough to be used on natural hair and chemically altered hair. Use of the products is recommended until the condition of the hair and scalp improves.

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What are some ways to recycle a television in Denver?

Due to federal regulations regarding the proper treatment and disposal of electronics, recycling organizations often have to pay a fee to dispose of electronics that cannot be salvaged or recycled. Fees are charged to people who drop off electronics to be recycled, except in certain circumstances. For example, Blue Star Recyclers does not charge a fee for recycling mobile phones, computers or laptops.

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What are ppm units?

One ppm is the same as 0.0001 percent by weight. With dilute substances, the weight of the trace portion is negligible, so it is equivalent to a concentration of one milligram per liter (mg/L) in a solution with water. Other measurement units for even more dilute substances are parts per billion (ppb) and even parts per trillion (which is not abbreviated, because ppt could also mean "parts per thousand," which would cause confusion).

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How do piezoelectric crystals work?

One of the best known uses of piezoelectric crystals is in a cigarette or a gas grill lighter, where pressing the button causes a spring-loaded hammer to strike the crystal. This pressure deforms the crystal and creates a high voltage that ignites the gas as the current jumps a small spark gap.\nThe auto focus in a digital camera also uses piezoelectric crystals, notes Green Energy Help Files. Vibrations applied at a certain frequency to two surfaces of the crystal create a force between them. One surface is fixed, and the other surface is forced to move.\nPiezoelectric crystals are used in bu..

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What are some tips for the phlebotomist order of draw?

Order of draw protects blood specimens from becoming contaminated, according to the website E-Phlebotomy Training. The order of draw is officially established by the Clinical Laboratory Standards Institute and covers any blood taken via collection tube, syringe, or evacuated system. Different blood tests require tubes containing different additives. These additives may contaminate other tests if proper order of draw is not followed.\nThe mnemonic "Boys Love Ravishing Girls Like Dieters Love Greek Yogurt," recommended by the website Phlebotomy Coach, helps phlebotomists remember the proper orde..

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