Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The most precarious of these quake-lakes was the one located in the extremely difficult terrain at Mount Tangjia in Beichuan County, Sichuan, accessible only by foot or air; an Mi-26T heavy lift helicopter belonging to the China Flying Dragon Special Aviation Company was used to bring heavy earthmoving tractors to the affected location. This operation was coupled with the work done by PLAAF Mi-17 helicopters bringing in PLA engineering corps, explosive specialists and other personnel to join 1,200 soldiers who arrived on site by foot. Five tons of fuel to operate the machinery was airlifted to the site, where a sluice was constructed to allow the safe discharge of the bottlenecked water. Downstream, more than 200,000 people were evacuated from Mianyang by June 1 in anticipation of the dam bursting.
How many soldiers had to travel to the area by foot?
A: 1,200

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Unpopulated boards are usually bare-board tested for "shorts" and "opens". A short is a connection between two points that should not be connected. An open is a missing connection between points that should be connected. For high-volume production a fixture or a rigid needle adapter is used to make contact with copper lands on the board. Building the adapter is a significant fixed cost and is only economical for high-volume or high-value production. For small or medium volume production flying probe testers are used where test probes are moved over the board by an XY drive to make contact with the copper lands. The CAM system instructs the electrical tester to apply a voltage to each contact point as required and to check that this voltage appears on the appropriate contact points and only on these.
A closed is a missing connection between what?
A: unanswerable

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Public opinion pressured the U.S. government to bring Villa to justice for the raid on Columbus, New Mexico; U.S. President Wilson sent Gen. John J. Pershing and some 5,000 troops into Mexico in an unsuccessful attempt to capture Villa. It was known as the Punitive Expedition. After nearly a year of pursuing Villa, American forces returned to the United States. The American intervention had been limited to the western sierras of Chihuahua. Villa had the advantage of intimately knowing the inhospitable terrain of the Sonoran Desert and the almost impassable Sierra Madre mountains and always managed to stay one step ahead of his pursuers. In 1923 Villa was assassinated by a group of seven gunmen who ambushed him while he was sitting in the back seat of his car in Parral.
How long did the American troops pursue Villa?
A: nearly a year

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Further along these lines, The ethical problems brought up by IP rights are most pertinent when it is socially valuable goods like life-saving medicines are given IP protection. While the application of IP rights can allow companies to charge higher than the marginal cost of production in order to recoup the costs of research and development, the price may exclude from the market anyone who cannot afford the cost of the product, in this case a life-saving drug. "An IPR driven regime is therefore not a regime that is conductive to the investment of R&D of products that are socially valuable to predominately poor populations".:11089
What do IP rights keep companies from recouping?
A:
unanswerable