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How tall is Mount Vesuvius?

Mount Vesuvius is famous for its destruction of Pompeii on August 24 A.D. 79. Thousands lost their lives during this eruption. During that volcanic activity, it also destroyed the cities of Herculaneum and Stabiae. Mount Vesuvius' Pompeii destruction was the first volcanic episode described by a third party, Pliny the Younger. It took until the 18th century before Pompeii and Herculaneum were unburied. Pompeii was under 10 feet of material, while Herculaneum was under 75 feet of ash.

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What is the difference between AC and DC motors?

AC and DC motors also differ in their construction. AC motors do not use brushes. DC motors use brushes. The use of brushes tends to increase maintenance, shorten the life expectancy and limits the speed of the motor. AC motors can withstand wear and tear and have a longer life span. DC and AC motors have differing means of speed control. While DC motors are controlled by varying the armature winding's current, AC motors simply vary the frequency.\nAn induction motor and a synchronous motor are two types of AC motors. An induction motor uses a magnetic field on a rotor that is created by ..

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How many tons are in a cubic yard?

A cubic yard of dry building sand weighs 1.09 tons. If the cubic yard is pure water, then the answer is 0.75 ton. A cubic yard of saltwater, meanwhile, weighs 0.77 ton. Due to the anomalous expansion of water, the weight of water changes depending on the temperature. A cubic yard of ice weighs only 0.69 ton, the same as a cubic yard at of water at 45 degrees Fahrenheit.

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What is the structure of an atom?

The mass of an atom is primarily determined by the number of protons and neutrons it has, as electrons have very little mass. Protons have a positive energy charge, electrons have a negative energy charge, and neutrons have no charge. The mass of an atom of a particular element may vary, as some atoms of the same element have different quantities of neutrons. These atoms are called isotopes.\nAtomic structure directly relates to an element’s physical and chemical properties. Every atom tries to have a full outer electron orbital, and those that don’t have full orbitals take part in chemica..

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What forces act on a parachute?

The influence of gravity and air resistance depend on several factors, including the shape of the parachute, size and weight of the parachutist, and the speed at which the parachute is falling. Generally, the smaller and lighter an object is, the rate at which it falls through the air is slower compared to an object of a larger size. This means that air resistance acts with a greater force on the smaller and lighter object, helping it remain in the air for longer periods of time. While air resistance works to keep parachutes in the air, gravity has the opposite effect. Gravity essentially pull..

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What type of doctor would you visit for earwax removal?

Earwax, or cerumen, protects, lubricates and cleans the ear. When functioning normally, the ear releases earwax naturally through jaw motion. One of the most common causes of earwax accumulation in the inner ear is external sources, such as cotton swabs, pushing the earwax into the ear drum. Otolaryngologists urge patients to use mineral oil, glycerin or over-the-counter ear drops to clean the inner ear rather than cotton swabs.

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What is genotyping by sequencing?

According to the Institute for Genomic Diversity at Cornell University, the GBS system is a simple but strictly ordered method of reducing genome repetitiveness and complexity. One of the ways it achieves this is by generating single nucleotide polymorphisms, or SNPs, in large numbers. Other important benefits of the GBS system are inexpensive bar coding, a decreased number of purification steps, reduced sample handling and no size fractionation.\nNext generation sequencing technologies are becoming increasingly important to genotyping by sequencing. GBS is a cost effective tool for studying g..

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What are the gravity numbers of all the planets?

A planet that is very massive exerts a huge gravitational force only if it is also very compact. The equation that describes gravitational force increases with mass and decreases significantly as the radius of the gravitating object grows. This is why the planet Jupiter, which is much more massive than Earth, only exerts 2.3 times Earth's gravitational pull.\nThe sun is an object that is far more massive than Jupiter and even though its radius is also bigger, it is still compact enough to have a gravity number of 27. An example of a very massive object with a very small radius is a white ..

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What is the chemical formula for glucose?

Glucose can be used by humans in a chemical reaction that combines glucose and oxygen to yield carbon dioxide and water. Energy for a wide variety of human body functions is readily available from the glucose in the blood.\nCertain medical conditions such as diabetes or hypoglycemia can present in humans that have too much or too little glucose in their blood. These conditions are often diagnosed by performing laboratory tests on an person's blood.

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What color is the planet Jupiter?

A faint system of three, thin rings made of tiny dust particles surrounds the planet. These rings were discovered by NASA with the Voyager 1 spacecraft in 1979.\nJupiter is a gas giant with an atmosphere mostly composed of hydrogen and helium. The planet has no solid surface, though it is believed to contain a solid core the size of Earth. Jupiter is the biggest planet in the solar system and is large enough to contain all of the other planets inside it.

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