Problem: Given the question: Extract the answer to the question from the following context. Question: What kind of transportation are Attitude Indicator (AI)s and Heading Indicatior (HI)s used in? Context: Manifold vacuum can be used to drive accessories on automobiles. The best-known application is the vacuum servo, used to provide power assistance for the brakes. Obsolete applications include vacuum-driven windscreen wipers and Autovac fuel pumps. Some aircraft instruments (Attitude Indicator (AI) and the Heading Indicator (HI)) are typically vacuum-powered, as protection against loss of all (electrically powered) instruments, since early aircraft often did not have electrical systems, and since there are two readily available sources of vacuum on a moving aircraftthe engine and an external venturi. Vacuum induction melting uses electromagnetic induction within a vacuum.
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The answer is:
aircraft

Problem: Given the question: Extract the answer to the question from the following context. Question: Timber is a form of? Context: New domestic housing in many parts of the world today is commonly made from timber-framed construction. Engineered wood products are becoming a bigger part of the construction industry. They may be used in both residential and commercial buildings as structural and aesthetic materials.
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The answer is:
wood products

Problem: Given the question: Extract the answer to the question from the following context. Question: How does this play out in history? Context: This change is interesting from a sociolinguistic point of view because it has apparently happened relatively recently, in the 1970s, and was pioneered by older well-educated women from the upper middle classes. The lowering of the diphthongs has long been current in many Dutch dialects, and is comparable to the English Great Vowel Shift, and the diphthongisation of long high vowels in Modern High German, which centuries earlier reached the state now found in Polder Dutch. Stroop theorizes that the lowering of open-mid to open diphthongs is a phonetically "natural" and inevitable development and that Dutch, after having diphthongised the long high vowels like German and English, "should" have lowered the diphthongs like German and English as well.
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The answer is:
is comparable to the English Great Vowel Shift