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Though still predominantly green, post-2004 series incorporate other colors to better distinguish different denominations. As a result of a 2008 decision in an accessibility lawsuit filed by the American Council of the Blind, the Bureau of Engraving and Printing is planning to implement a raised tactile feature in the next redesign of each note, except the $1 and the version of the $100 bill already in process. It also plans larger, higher-contrast numerals, more color differences, and distribution of currency readers to assist the visually impaired during the transition period.
Who are transition periods meant to assist?
A: unanswerable

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The late Georgian period saw the birth of the semi-detached house, planned systematically, as a suburban compromise between the terraced houses of the city and the detached "villas" further out, where land was cheaper. There had been occasional examples in town centres going back to medieval times. Most early suburban examples are large, and in what are now the outer fringes of Central London, but were then in areas being built up for the first time. Blackheath, Chalk Farm and St John's Wood are among the areas contesting being the original home of the semi. Sir John Summerson gave primacy to the Eyre Estate of St John's Wood. A plan for this exists dated 1794, where "the whole development consists of pairs of semi-detached houses, So far as I know, this is the first recorded scheme of the kind". In fact the French Wars put an end to this scheme, but when the development was finally built it retained the semi-detached form, "a revolution of striking significance and far-reaching effect".
What type of house was born in the early Georgian period?
A: unanswerable

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After 1870, the new railroads across the Plains brought hunters who killed off almost all the bison for their hides. The railroads offered attractive packages of land and transportation to European farmers, who rushed to settle the land. They (and Americans as well) also took advantage of the homestead laws to obtain free farms. Land speculators and local boosters identified many potential towns, and those reached by the railroad had a chance, while the others became ghost towns. In Kansas, for example, nearly 5000 towns were mapped out, but by 1970 only 617 were actually operating. In the mid-20th century, closeness to an interstate exchange determined whether a town would flourish or struggle for business.
In what year were the homestead laws passed?
A: unanswerable

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In 1988, only 60,000 computers were connected to the Internet, and most were mainframes, minicomputers and professional workstations. On November 2, 1988, many started to slow down, because they were running a malicious code that demanded processor time and that spread itself to other computers the first internet "computer worm". The software was traced back to 23-year-old Cornell University graduate student Robert Tappan Morris, Jr. who said 'he wanted to count how many machines were connected to the Internet'.
Who tracked down the first computer worm?
A:
unanswerable