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Electric railways use electric locomotives to haul passengers or freight in separate cars or electric multiple units, passenger cars with their own motors. Electricity is typically generated in large and relatively efficient generating stations, transmitted to the railway network and distributed to the trains. Some electric railways have their own dedicated generating stations and transmission lines but most purchase power from an electric utility. The railway usually provides its own distribution lines, switches and transformers.
Very few purchase power from whom?
A: unanswerable

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The Americo-Liberian settlers did not identify with the indigenous peoples they encountered, especially those in communities of the more isolated "bush." They knew nothing of their cultures, languages or animist religion. Encounters with tribal Africans in the bush often developed as violent confrontations. The colonial settlements were raided by the Kru and Grebo people from their inland chiefdoms. Because of feeling set apart and superior by their culture and education to the indigenous peoples, the Americo-Liberians developed as a small elite that held on to political power. It excluded the indigenous tribesmen from birthright citizenship in their own lands until 1904, in a repetition of the United States' treatment of Native Americans. Because of the cultural gap between the groups and assumption of superiority of western culture, the Americo-Liberians envisioned creating a western-style state to which the tribesmen should assimilate. They encouraged religious organizations to set up missions and schools to educate the indigenous peoples.
What did the indigenous peoples envision creating?
A: unanswerable

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Philosophical empiricists hold no knowledge to be properly inferred or deduced unless it is derived from one's sense-based experience. This view is commonly contrasted with rationalism, which states that knowledge may be derived from reason independently of the senses. For example, John Locke held that some knowledge (e.g. knowledge of God's existence) could be arrived at through intuition and reasoning alone. Similarly Robert Boyle, a prominent advocate of the experimental method, held that we have innate ideas. The main continental rationalists (Descartes, Spinoza, and Leibniz) were also advocates of the empirical "scientific method".
Who were the main philosophical empiricists?
A: unanswerable

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Animals typically use the color green as camouflage, blending in with the chlorophyll green of the surrounding environment. Green animals include, especially, amphibians, reptiles, and some fish, birds and insects. Most fish, reptiles, amphibians, and birds appear green because of a reflection of blue light coming through an over-layer of yellow pigment. Perception of color can also be affected by the surrounding environment. For example, broadleaf forests typically have a yellow-green light about them as the trees filter the light. Turacoverdin is one chemical which can cause a green hue in birds, especially. Invertebrates such as insects or mollusks often display green colors because of porphyrin pigments, sometimes caused by diet. This can causes their feces to look green as well. Other chemicals which generally contribute to greenness among organisms are flavins (lychochromes) and hemanovadin. Humans have imitated this by wearing green clothing as a camouflage in military and other fields. Substances that may impart a greenish hue to one's skin include biliverdin, the green pigment in bile, and ceruloplasmin, a protein that carries copper ions in chelation.
What is another name for hemanovadin?
A:
unanswerable