Problem: Printed circuit board:

Moisture absorption occurs when the material is exposed to high humidity or water. Both the resin and the reinforcement may absorb water; water may be also soaked by capillary forces through voids in the materials and along the reinforcement. Epoxies of the FR-4 materials aren't too susceptible, with absorption of only 0.15%. Teflon has very low absorption of 0.01%. Polyimides and cyanate esters, on the other side, suffer from high water absorption. Absorbed water can lead to significant degradation of key parameters; it impairs tracking resistance, breakdown voltage, and dielectric parameters. Relative dielectric constant of water is about 73, compared to about 4 for common circuitboard materials. Absorbed moisture can also vaporize on heating and cause cracking and delamination, the same effect responsible for "popcorning" damage on wet packaging of electronic parts. Careful baking of the substrates may be required.

Teflon has a high absorption rate of what?
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A: unanswerable


Problem: Freemasonry:

Prince Hall Freemasonry exists because of the refusal of early American lodges to admit African-Americans. In 1775, an African-American named Prince Hall, along with fourteen other African-Americans, was initiated into a British military lodge with a warrant from the Grand Lodge of Ireland, having failed to obtain admission from the other lodges in Boston. When the military Lodge left North America, those fifteen men were given the authority to meet as a Lodge, but not to initiate Masons. In 1784, these individuals obtained a Warrant from the Premier Grand Lodge of England (GLE) and formed African Lodge, Number 459. When the UGLE was formed in 1813, all U.S.-based Lodges were stricken from their rolls – due largely to the War of 1812. Thus, separated from both UGLE and any concordantly recognised U.S. Grand Lodge, African Lodge re-titled itself as the African Lodge, Number 1 – and became a de facto "Grand Lodge" (this Lodge is not to be confused with the various Grand Lodges on the Continent of Africa). As with the rest of U.S. Freemasonry, Prince Hall Freemasonry soon grew and organised on a Grand Lodge system for each state.

When was Prince Hall Freemasonry forgotten?
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A: unanswerable


Problem: Police:

Police development-aid to weak, failed or failing states is another form of transnational policing that has garnered attention. This form of transnational policing plays an increasingly important role in United Nations peacekeeping and this looks set to grow in the years ahead, especially as the international community seeks to develop the rule of law and reform security institutions in States recovering from conflict (Goldsmith and Sheptycki, 2007) With transnational police development-aid the imbalances of power between donors and recipients are stark and there are questions about the applicability and transportability of policing models between jurisdictions (Hills, 2009).

Who wrote about police development-aid in 2006?
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A: unanswerable


Problem: Southampton:

Southampton's police service is provided by Hampshire Constabulary. The main base of the Southampton operation is a new, eight storey purpose-built building which cost £30 million to construct. The building, located on Southern Road, opened in 2011 and is near to Southampton Central railway station. Previously, the central Southampton operation was located within the west wing of the Civic Centre, however the ageing facilities and the plans of constructing a new museum in the old police station and magistrates court necessitated the move. There are additional police stations at Portswood, Banister Park, Bitterne, and Shirley as well as a British Transport Police station at Southampton Central railway station.

How much did it cost to build the operations base of Southampton's police service?
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A:
£30 million