input question: Extract the answer to the question from the following context. Question: Which of the following is not a type of momemtum: angular, curvature or linear? Context: Mach argued that, in effect, the water experiment in an otherwise empty universe would remain flat. But if another object were introduced into this universe, perhaps a distant star, there would now be something relative to which the bucket could be seen as rotating. The water inside the bucket could possibly have a slight curve. To account for the curve that we observe, an increase in the number of objects in the universe also increases the curvature in the water. Mach argued that the momentum of an object, whether angular or linear, exists as a result of the sum of the effects of other objects in the universe (Mach's Principle).???
output answer: curvature

Extract the answer to the question from the following context. Question: Who visited St Helena closest to 1979? Context: One commentator has observed that, notwithstanding the high unemployment resulting from the loss of full passports during 1981–2002, the level of loyalty to the British monarchy by the St Helena population is probably not exceeded in any other part of the world. King George VI is the only reigning monarch to have visited the island. This was in 1947 when the King, accompanied by Queen Elizabeth (later the Queen Mother), Princess Elizabeth (later Queen Elizabeth II) and Princess Margaret were travelling to South Africa. Prince Philip arrived at St Helena in 1957 and then his son Prince Andrew visited as a member of the armed forces in 1984 and his sister the Princess Royal arrived in 2002.
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Answer: Prince Andrew

Q: Extract the answer to the question from the following context. Question: What does a country use to protect themselves from outside threat? Context: If the highest echelons of the governments also take advantage from corruption or embezzlement from the state's treasury, it is sometimes referred with the neologism kleptocracy. Members of the government can take advantage of the natural resources (e.g., diamonds and oil in a few prominent cases) or state-owned productive industries. A number of corrupt governments have enriched themselves via foreign aid, which is often spent on showy buildings and armaments.
A: armaments

Question: Extract the answer to the question from the following context. Question: What was used as the solution? Context: The tide-predicting machine invented by Sir William Thomson in 1872 was of great utility to navigation in shallow waters. It used a system of pulleys and wires to automatically calculate predicted tide levels for a set period at a particular location.
Answer: The tide-predicting machine

[Q]: Extract the answer to the question from the following context. Question: How much of the native population spoke Greek throughout the Hellenistic World? Context: Throughout the Hellenistic world, these Greco-Macedonian colonists considered themselves by and large superior to the native "barbarians" and excluded most non-Greeks from the upper echelons of courtly and government life. Most of the native population was not Hellenized, had little access to Greek culture and often found themselves discriminated against by their Hellenic overlords. Gymnasiums and their Greek education, for example, were for Greeks only. Greek cities and colonies may have exported Greek art and architecture as far as the Indus, but these were mostly enclaves of Greek culture for the transplanted Greek elite. The degree of influence that Greek culture had throughout the Hellenistic kingdoms was therefore highly localized and based mostly on a few great cities like Alexandria and Antioch. Some natives did learn Greek and adopt Greek ways, but this was mostly limited to a few local elites who were allowed to retain their posts by the Diadochi and also to a small number of mid-level administrators who acted as intermediaries between the Greek speaking upper class and their subjects. In the Seleucid empire for example, this group amounted to only 2.5 percent of the official class.
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[A]: Some

Problem: Given the question: Extract the answer to the question from the following context. Question: What moves horizontally? Context: Many birds show plumage patterns in ultraviolet that are invisible to the human eye; some birds whose sexes appear similar to the naked eye are distinguished by the presence of ultraviolet reflective patches on their feathers. Male blue tits have an ultraviolet reflective crown patch which is displayed in courtship by posturing and raising of their nape feathers. Ultraviolet light is also used in foraging—kestrels have been shown to search for prey by detecting the UV reflective urine trail marks left on the ground by rodents. The eyelids of a bird are not used in blinking. Instead the eye is lubricated by the nictitating membrane, a third eyelid that moves horizontally. The nictitating membrane also covers the eye and acts as a contact lens in many aquatic birds. The bird retina has a fan shaped blood supply system called the pecten. Most birds cannot move their eyes, although there are exceptions, such as the great cormorant. Birds with eyes on the sides of their heads have a wide visual field, while birds with eyes on the front of their heads, such as owls, have binocular vision and can estimate the depth of field. The avian ear lacks external pinnae but is covered by feathers, although in some birds, such as the Asio, Bubo and Otus owls, these feathers form tufts which resemble ears. The inner ear has a cochlea, but it is not spiral as in mammals.
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The answer is:
a third eyelid