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How does snow form and fall?

As water droplets freeze and form crystals, they make up symmetrical six-sided patterns that vary according to the temperature. For instance, snowflakes forming at 23 degrees Fahrenheit tend to have longer, thinner appendages, while snowflakes at colder temperatures form in flat patterns. The biggest snowflakes normally measure at less than 1/2 inch across, but if snowflakes clump and freeze together, they can reach almost 2 inches in diameter.\nBecause moisture is a basic requirement to the formation of snow, snowfall is heavier in humid and moist areas. An area in Antarctica that gets very l..

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How long is winter?

In the northern hemisphere, the winter solstice is December 21 or 22. It is also the shortest day of the year, as the Earth is tilted so that the southern hemisphere receives more daylight. In astronomical terms, it means the sun is the farthest away from the celestial equator, which is an imaginary line that runs around the earth above the equator. The same day marks the summer solstice in the southern hemisphere. Alternatively, the spring equinox signals the beginning of spring. It is always March 20 or 21. Therefore, in the northern hemisphere, winter lasts from December 21 or 22 to March 2..

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Why does adding salt to water increases its density?

To study density of different substances, it is convenient to compare two containers, where one container has plain water, and the other container has salt, or sodium chloride and water. In this experiment, both containers have equal amounts of water. The container that holds the water has the mass of water only. However, the saltwater mixture contains the added mass of sodium and chloride ions. This causes this mixture to have a greater mass while the volume changes by a slight amount. Using the density formula, it is evident that the salt-water mixture with a greater mass and a volume change..

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What are examples of the class Agnatha?

Most members of the class Agnatha lack pairs of fins, another distinguishing characteristic. Some, like lampreys, exist as parasitic species. Lampreys attach to host fish. They do so using strong jaws with teeth resembling tiny hooks. After embedding their teeth into the skin of host fish, lampreys remove tissue and vital fluids. This eventually weakens and kills their hosts, while providing food and sustenance for lampreys. Lampreys begin their lives as larvae, living primarily in freshwater environments. Upon reaching maturity, they might remain in freshwater habitats or migrate to ocean wat..

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What do trees provide?

Trees also clean the air and filter airborne pollutants. Trees can reduce utility bills if they are placed in the right spot by providing shade on a house. Trees that are fruit bearing also provide food for animals and humans. Trees also provide shade in parking lots for cars. By doing this, they reduce ozone emissions from vehicles. Trees can also block out noise pollution because they will absorb sound, and they also help provide hundreds of different animals a habitat to live in.

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How do you measure wavelength?

A crest is the highest point of the wavelength curve, and the trough is the lowest point of the wavelength curve. A wave can be measured using frequency because the higher the frequency of the signal, the shorter the wavelength. As wavelength is inversely related to frequency, another way to measure the wavelength is to divide the frequency of the waves (oscillations) by the speed of the wave, in so far that wavelength equals speed/frequency.

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What is the Earth's motion that causes day and night?

At any given time, half of the earth is cast in the shadow of darkness while the other half is bathed in light. The earth rotates vertically but shifts horizontally too: this tilt accounts for prolonged changes in light and darkness that coincide with changing seasons. The daily patterns of sunrise, noon and sunset at all points on earth are heavily influenced by the 24-hour rotation cycle, which causes different conditions simultaneously around the globe. Although some days have fewer hours of sunlight and others longer, the difference averages out so that all areas of earth have equal times ..

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What is the difference between an allele and a gene?

Different types of organisms organize their DNA in slightly different ways. Most of the time, the DNA is grouped into several different pieces called chromosomes. Humans, for example, have 46 chromosomes. Because humans reproduce sexually, 23 of the chromosomes come from the organism’s mother and 23 come from its father. Other organisms have different numbers of chromosomes, such as some crayfish that have 200 chromosomes or fruit flies, which have eight chromosomes.\nDiscrete parts of each chromosome — the genes — control different aspects of the animal or plant’s structure or functio..

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What kind of joint is the knee?

Healthline explains that the complete knee joint is a complex mechanism composed of muscles, ligaments, tendons and bones. The joint capsule allows the knee to bend and is held together by ligaments, which also act to flex the leg. The cartilage pads, or menisci, disperse friction between the meeting ends of the femur and tibia. Synovial fluid inside the joint capsule acts as a lubricant and is secreted by the synovial tissue, according to Johns Hopkins.

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What element has a nuclear charge of 45?

Rhodium has low electrical resistance but high resistance to corrosion. This is why it is used to coat optic fibres, form thermocouple elements and aid in the production of headlight reflectors. It is predominantly needed in the manufacture of catalytic converters but also finds purpose in the crafting of jewellery.\nRhodium is a transition metal whose name comes from the Greek word for rose. It has no known biological function.

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