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What are some facts about the moon?

The Moon was formed about 4.5 billion years ago, during the early history of the solar system, when a Mars-sized planet struck the early Earth. This off-center collision ejected tremendous amounts of material from the Earth's mantle at escape velocity. In time, the material accreted into what would become known as the Moon. At first, the Moon was much closer to the Earth than it is today.\nThe Moon has been drifting away from the Earth since its formation, and it will continue this drift long into the future. One peculiar coincidence that has arisen as a result of this drift is that the p..

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What is a photogate timer?

Most photogate timers have a selectable resolution switch that gives the user the ability to select the sensitivity of the timer. Photogate timers are relativity inexpensive and easy to use, requiring standard AC power adapters or battery cells to function. They are usually used in physics labs to conduct experiments involving the measurement of instantaneous versus average velocity, the force of gravity, pendulum motion and the speed of a projectile. The device measures the velocity of objects by using an infrared diode and photocell. Timing occurs when an object interrupts the infrared beam ..

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What is 4 p.m. Eastern time in GMT?

During the summer, which is when U.S. clocks are on daylight savings time in most states, GMT time is four hours ahead of EDT. During the winter, when daylight savings time is not in effect, GMT is five hours ahead of EST because one hour is gained in setting the clocks backward during the switch to standard time. The EST time zone covers the east coast of the United States.

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What causes clematis leaves to turn yellow?

Clematis wilt affects the stem, causing the foliage to wilt, whereas rust affects the leaves, causing orange or yellowish spots to appear on them. Both whiteflies and aphids feed on clematis leaves, causing them to curl towards the stem, but scales feed on branches, leading to leaf wilting and leaf drop. Over-watering causes overall yellowing of the leaves, and under-watering causes browning of the leaf tips. Lastly, over-fertilization burns both the roots and leaves of the clematis.

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How does electronegativity vary within groups and across periods?

There are several exceptions to the general trends of electronegativity in the periodic table. The first is the element hydrogen, which is a group 1 element. Its electronegativity is over twice as high as the next element down, lithium.\nNoble gases, however, are an exception to the rule as a group. Electronegativity is largely irrelevant to the noble gases helium, neon, argon, krypton, xenon and radon. Under normal conditions, these elements have no tendency to attract electrons nor any tendency to lose them because they have a full valence shell. They are unreactive, outside of extreme condi..

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Where does ricin come from?

Processed castor beans produce castor oil, a substance used around the world. Once the castor beans have been processed, a "waste" substance remains, which is where ricin is found. Intact castor beans do not release ricin; only when the beans are broken is ricin released.\nWhen ricin enters the body, it goes to the cells and works on the ribosomes, the protein-making structures in cells. Proteins are not made, so cells die because all life processes are dependent on proteins.

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What are some carbon sequestration methods?

Terrestrial sequestration stores the carbon taken from captured carbon dioxide in the soil and the roots and stems of plants. Geologic sequestration captures carbon dioxide before it is released into the atmosphere from anthropogenic sources and transports it deep underground to aging oil fields or saline aquifers. Because CO2 is heavier than water, and it remains in liquid forms at great depths, pumping it to the bottom of the ocean is another possibility.

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How do insects excrete waste?

Insects eat food through their mouths, which vary in structure according to the type of food they eat. The food then passes through the foregut, where salivary glands help lubricate the item. It is further digested as it passes caudally through the midgut and then the hindgut. The rectum exits the back of the abdomen through a structure called the anus.\nInsects are efficient with water. When digested food passes into the rectum, up to 90 percent of the water is reabsorbed to prevent dehydration. Rather than producing urine, insects use a system of structures called Malpighian tubules to remov..

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What is the difference between a nucleoside and a nucleotide?

Genetics, the study of heredity, focuses on how certain traits are passed to offspring from their parents. Traits include physical characteristics, such as eye color, height, skin color and hair type. Sometimes, mutations are passed from parents to offspring, resulting in extra appendages or additional chromosomes. It is possible for mutations to cause no issues for the offspring, but they are also known to cause genetic disorders, such as cystic fibrosis and autism.

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What is a nandina shrub?

The nandina shrub is a decorative plant that produces bright red berries in the fall and winter that are slightly toxic when eaten, according to North Carolina State University. Nandina shrubs have small white flowers that bloom in June, and their leaves alternate on the branches. The bright colors are great as an ornamental addition to a garden or landscape. They grow up to 8 feet high and three feet across, making them a good option for hedges in landscaping.\nA versatile shrub, the nandina has a medium need for water and can thrive in direct sun or partial shade. The hardy structure means t..

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