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Machine vision systems often require bright and homogeneous illumination, so features of interest are easier to process. LEDs are often used for this purpose, and this is likely to remain one of their major uses until the price drops low enough to make signaling and illumination uses more widespread. Barcode scanners are the most common example of machine vision, and many low cost products use red LEDs instead of lasers. Optical computer mice are an example of LEDs in machine vision, as it is used to provide an even light source on the surface for the miniature camera within the mouse. LEDs constitute a nearly ideal light source for machine vision systems for several reasons:
What can't help make LEDs more widely used?
A: unanswerable

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The Namibian Constitution adopted in February 1990 incorporated protection for human rights, compensation for state expropriations of private property, an independent judiciary and an executive presidency (the constituent assembly became the national assembly). The country officially became independent on 21 March 1990. Sam Nujoma was sworn in as the first President of Namibia watched by Nelson Mandela (who had been released from prison the previous month) and representatives from 147 countries, including 20 heads of state. Walvis Bay was ceded to Namibia in 1994 upon the end of Apartheid in South Africa.[citation needed]
What was one of the countries that sent a head of state to Namibia for the first presidential swearing-in?
A: unanswerable

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The First Great Awakening was an evangelical and revitalization movement that swept through Protestant Europe and British America, especially the American colonies in the 1730s and 1740s, leaving a permanent impact on American Protestantism. It resulted from powerful preaching that gave listeners a sense of deep personal revelation of their need of salvation by Jesus Christ. Pulling away from ritual, ceremony, sacramentalism and hierarchy, it made Christianity intensely personal to the average person by fostering a deep sense of spiritual conviction and redemption, and by encouraging introspection and a commitment to a new standard of personal morality.
What movement made a permanent mark on Protestantism in the U.S.?
A: The First Great Awakening

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The first major model for communication was introduced by Claude Shannon and Warren Weaver for Bell Laboratories in 1949 The original model was designed to mirror the functioning of radio and telephone technologies. Their initial model consisted of three primary parts: sender, channel, and receiver. The sender was the part of a telephone a person spoke into, the channel was the telephone itself, and the receiver was the part of the phone where one could hear the other person. Shannon and Weaver also recognized that often there is static that interferes with one listening to a telephone conversation, which they deemed noise.
What was the channel in the initial model?
A:
the telephone itself