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In 1877, John Wanamaker opened the United State's first modern department store in a former Pennsylvania Railroad freight terminal in Philadelphia. Wanamakers was the first department store to offer fixed prices marked on every article and also introduced electrical illumination (1878), the telephone (1879), and the use of pneumatic tubes to transport cash and documents (1880) to the department store business. Subsequent department stores founded in Philadelphia included Strawbridge and Clothier, Gimbels, Lit Brothers, and Snellenbergs.
When was electric lighting first installed and used in the store? 
A: 1878

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Operating at normal power line frequencies, universal motors are often found in a range less than 1000 watts. Universal motors also formed the basis of the traditional railway traction motor in electric railways. In this application, the use of AC to power a motor originally designed to run on DC would lead to efficiency losses due to eddy current heating of their magnetic components, particularly the motor field pole-pieces that, for DC, would have used solid (un-laminated) iron and they are now rarely used.
What were universal motor pole pieces constructed from?
A: solid (un-laminated) iron

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Solar energy is radiant light and heat from the Sun harnessed using a range of ever-evolving technologies such as solar heating, photovoltaics, solar thermal energy, solar architecture and artificial photosynthesis.
What technologies are used to harness solar energy from the sun?
A: solar heating, photovoltaics, solar thermal energy, solar architecture and artificial photosynthesis

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Endemic species can be threatened with extinction through the process of genetic pollution, i.e. uncontrolled hybridization, introgression and genetic swamping. Genetic pollution leads to homogenization or replacement of local genomes as a result of either a numerical and/or fitness advantage of an introduced species. Hybridization and introgression are side-effects of introduction and invasion. These phenomena can be especially detrimental to rare species that come into contact with more abundant ones. The abundant species can interbreed with the rare species, swamping its gene pool. This problem is not always apparent from morphological (outward appearance) observations alone. Some degree of gene flow is normal adaptation, and not all gene and genotype constellations can be preserved. However, hybridization with or without introgression may, nevertheless, threaten a rare species' existence.
What can threaten endemic species with extinction?
A:
genetic pollution