input: Please answer the following: Extract the answer to the question from the following context. Question: What is Rayleigh scattering? Context: In nature, the red color of blood comes from hemoglobin, the iron-containing protein found in the red blood cells of all vertebrates. The red color of the Grand Canyon and other geological features is caused by hematite or red ochre, both forms of iron oxide. It also causes the red color of the planet Mars. The red sky at sunset and sunrise is caused by an optical effect known as Rayleigh scattering, which, when the sun is low or below the horizon, increases the red-wavelength light that reaches the eye. The color of autumn leaves is caused by pigments called anthocyanins, which are produced towards the end of summer, when the green chlorophyll is no longer produced. One to two percent of the human population has red hair; the color is produced by high levels of the reddish pigment pheomelanin (which also accounts for the red color of the lips) and relatively low levels of the dark pigment eumelanin.
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output: optical effect

Please answer this: Extract the answer to the question from the following context. Question: A bit is a unit of? Context: USB data is transmitted by toggling the data lines between the J state and the opposite K state. USB encodes data using the NRZI line coding; a 0 bit is transmitted by toggling the data lines from J to K or vice versa, while a 1 bit is transmitted by leaving the data lines as-is. To ensure a minimum density of signal transitions remains in the bitstream, USB uses bit stuffing; an extra 0 bit is inserted into the data stream after any appearance of six consecutive 1 bits. Seven consecutive received 1 bits is always an error. USB 3.0 has introduced additional data transmission encodings.
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Answer: data

Problem: Extract the answer to the question from the following context. Question: What is the major hub? Context: Richmond is a major hub for intercity bus company Greyhound Lines, with its terminal at 2910 N Boulevard. Multiple runs per day connect directly with Washington, D.C., New York, Raleigh, and elsewhere. Direct trips to New York take approximately 7.5 hours. Discount carrier Megabus also provides curbside service from outside of Main Street Station, with fares starting at $1. Direct service is available to Washington, D.C., Hampton Roads, Charlotte, Raleigh, Baltimore, and Philadelphia. Most other connections to Megabus served cites, such as New York, can be made from Washington, D.C. Richmond, and the surrounding metropolitan area, was granted[when?] a roughly $25 million grant from the U.S. Department of Transportation to support a newly proposed Rapid Transit System, which would run along Broad Street from Willow Lawn to Rocketts Landing, in the first phase of an improved public transportation hub for the region.

A: Richmond

Problem: Given the question: Extract the answer to the question from the following context. Question: What do antibacterial compounds work against? Context: Several molecular mechanisms of antibacterial resistance exist. Intrinsic antibacterial resistance may be part of the genetic makeup of bacterial strains. For example, an antibiotic target may be absent from the bacterial genome. Acquired resistance results from a mutation in the bacterial chromosome or the acquisition of extra-chromosomal DNA. Antibacterial-producing bacteria have evolved resistance mechanisms that have been shown to be similar to, and may have been transferred to, antibacterial-resistant strains. The spread of antibacterial resistance often occurs through vertical transmission of mutations during growth and by genetic recombination of DNA by horizontal genetic exchange. For instance, antibacterial resistance genes can be exchanged between different bacterial strains or species via plasmids that carry these resistance genes. Plasmids that carry several different resistance genes can confer resistance to multiple antibacterials. Cross-resistance to several antibacterials may also occur when a resistance mechanism encoded by a single gene conveys resistance to more than one antibacterial compound.
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The answer is:
bacteria

input question: Extract the answer to the question from the following context. Question: Why did Bell's father decline the offer to introduce the Visible Speech System? Context: Bell's father was invited by Sarah Fuller, principal of the Boston School for Deaf Mutes (which continues today as the public Horace Mann School for the Deaf), in Boston, Massachusetts, to introduce the Visible Speech System by providing training for Fuller's instructors, but he declined the post in favor of his son. Traveling to Boston in April 1871, Bell proved successful in training the school's instructors. He was subsequently asked to repeat the program at the American Asylum for Deaf-mutes in Hartford, Connecticut, and the Clarke School for the Deaf in Northampton, Massachusetts.???
output answer: in favor of his son

input question: Extract the answer to the question from the following context. Question: What metal is used? Context: The Faraday constant F is the charge of one mole of electrons, equal to the Avogadro constant NA multiplied by the elementary charge e. It can be determined by careful electrolysis experiments, measuring the amount of silver dissolved from an electrode in a given time and for a given electric current. In practice, it is measured in conventional electrical units, and so given the symbol F90. Substituting the definitions of NA and e, and converting from conventional electrical units to SI units, gives the relation to the Planck constant.???
output answer:
silver