Problem: Printed circuit board:

Other platings used are OSP (organic surface protectant), immersion silver (IAg), immersion tin, electroless nickel with immersion gold coating (ENIG), electroless nickel electroless palladium immersion gold (ENEPIG) and direct gold plating (over nickel). Edge connectors, placed along one edge of some boards, are often nickel plated then gold plated. Another coating consideration is rapid diffusion of coating metal into Tin solder. Tin forms intermetallics such as Cu5Sn6 and Ag3Cu that dissolve into the Tin liquidus or solidus(@50C), stripping surface coating or leaving voids.

What might the rapid diffusion of coating metal into tin solder leave in the surface coating?
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A: voids

Problem: On June 22, 1990, Volodymyr Ivashko withdrew his candidacy for leader of the Communist Party of Ukraine in view of his new position in parliament. Stanislav Hurenko was elected first secretary of the CPU. On July 11, Ivashko resigned from his post as chairman of the Ukrainian Parliament after he was elected deputy general secretary of the Communist Party of the Soviet Union. The Parliament accepted the resignation a week later, on July 18. On July 16 Parliament overwhelmingly approved the Declaration on State Sovereignty of Ukraine - with a vote of 355 in favour and four against. The people's deputies voted 339 to 5 to proclaim July 16 a Ukrainian national holiday.
How many Parliament members voted against the Declaration on State Sovereignty of Ukraine?
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Answer: four

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The current Chief of the Defence Staff, the professional head of the British Armed Forces, is General Sir Nicholas Houghton, late Green Howards. He is supported by the Vice Chief of the Defence Staff, by the professional heads of the three services of HM Armed Forces and by the Commander of Joint Forces Command.
Who is the current Commander of Joint Forces Command?
A: unanswerable

Context and question: To clean up pollution, the federal and local governments implemented numerous plans including the constant monitoring and reporting of environmental conditions, such as ozone and nitrogen oxides. When the levels of these two pollutants reached critical levels, contingency actions were implemented which included closing factories, changing school hours, and extending the A day without a car program to two days of the week. The government also instituted industrial technology improvements, a strict biannual vehicle emission inspection and the reformulation of gasoline and diesel fuels. The introduction of Metrobus bus rapid transit and the Ecobici bike-sharing were among efforts to encourage alternate, greener forms of transportation.
What is the bike-sharing program called in Mexico City?
Answer: Ecobici

Question: Montana i/mntn/ is a state in the Western region of the United States. The state's name is derived from the Spanish word montana (mountain). Montana has several nicknames, although none official, including "Big Sky Country" and "The Treasure State", and slogans that include "Land of the Shining Mountains" and more recently "The Last Best Place". Montana is ranked 4th in size, but 44th in population and 48th in population density of the 50 United States. The western third of Montana contains numerous mountain ranges. Smaller island ranges are found throughout the state. In total, 77 named ranges are part of the Rocky Mountains.
Is there an answer to this question: What is the states rank in size?

Answer: 4th

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Richard Nixon used national security as a basis for his expansion of power. He asserted, for example, that "the inherent power of the President to safeguard the security of the nation" authorized him to order a wiretap without a judge's warrant. Nixon also asserted that "executive privilege" shielded him from all legislative oversight; furthermore, he impounded federal funds (that is to say, he refused to spend money that Congress had appropriated for government programs). In the specific cases aforementioned, however, the Supreme Court ruled against Nixon. This was also because of an ongoing criminal investigation into the Watergate tapes, even though they acknowledged the general need for executive privilege. Since then, Nixon's successors have sometimes asserted that they may act in the interests of national security or that executive privilege shields them from Congressional oversight. Though such claims have in general been more limited than Nixon's, one may still conclude that the presidency's power has been greatly augmented since the eighteenth and nineteenth centuries.
Into which tapes was there an ongoing civil investigation?
A:
unanswerable