Problem: Guinea-Bissau:

Guinea-Bissau has started to show some economic advances after a pact of stability was signed by the main political parties of the country, leading to an IMF-backed structural reform program. The key challenges for the country in the period ahead are to achieve fiscal discipline, rebuild public administration, improve the economic climate for private investment, and promote economic diversification. After the country became independent from Portugal in 1974 due to the Portuguese Colonial War and the Carnation Revolution, the rapid exodus of the Portuguese civilian, military, and political authorities resulted in considerable damage to the country's economic infrastructure, social order, and standard of living.

What country left Guinea-Bissau in 1974?
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A: Portugal

Problem: Mandolin:

The transition from the mandolino to the mandolin began around 1744 with the designing of the metal-string mandolin by the Vinaccia family, 3 brass strings and one of gut, using friction tuning pegs on a fingerboard that sat "flush" with the sound table. The mandolin grew in popularity over the next 60 years, in the streets where it was used by young men courting and by street musicians, and in the concert hall. After the Napoleonic Wars of 1815, however, its popularity began to fall. The 19th century produced some prominent players, including Bartolomeo Bortolazzi of Venice and Pietro Vimercati. However, professional virtuosity was in decline, and the mandolin music changed as the mandolin became a folk instrument; "the large repertoire of notated instrumental music for the mandolino and the mandoline was completely forgotten". The export market for mandolins from Italy dried up around 1815, and when Carmine de Laurentiis wrote a mandolin method in 1874, the Music World magazine wrote that the mandolin was "out of date." Salvador Leonardi mentioned this decline in his 1921 book, Methode pour Banjoline ou Mandoline-Banjo, saying that the mandolin had been declining in popularity from previous times.

Who were two of the prominent players in the 15th century?
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A: unanswerable

Problem: Muslim world:

A Latin translation of Ibn Tufail's work, Philosophus Autodidactus, first appeared in 1671, prepared by Edward Pococke the Younger, followed by an English translation by Simon Ockley in 1708, as well as German and Dutch translations. These translations might have later inspired Daniel Defoe to write Robinson Crusoe, regarded as the first novel in English. Philosophus Autodidactus, continuing the thoughts of philosophers such as Aristotle from earlier ages, inspired Robert Boyle to write his own philosophical novel set on an island, The Aspiring Naturalist.

Who wrote Robinson Crusoe?
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A: Daniel Defoe

Problem: Printed circuit board:

Multi-layer printed circuit boards have trace layers inside the board. This is achieved by laminating a stack of materials in a press by applying pressure and heat for a period of time. This results in an inseparable one piece product. For example, a four-layer PCB can be fabricated by starting from a two-sided copper-clad laminate, etch the circuitry on both sides, then laminate to the top and bottom pre-preg and copper foil. It is then drilled, plated, and etched again to get traces on top and bottom layers.

If you started with a two-sided laminate etched on either side, laminated to the top and bottom, and processed it again to get traces on the outside layers, how many layers would your final PCB have?
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A:
four