Problem: Given the question: Extract the answer to the question from the following context. Question: What can help assist cars in stopping suddenly? 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 aircraft—the engine and an external venturi. Vacuum induction melting uses electromagnetic induction within a vacuum.
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The answer is:
brakes


Problem: Given the question: Extract the answer to the question from the following context. Question: The thing that theorists suggested to have something to do with external and internal event, how did they discribe it? Context: Emotions have been described by some theorists as discrete and consistent responses to internal or external events which have a particular significance for the organism. Emotions are brief in duration and consist of a coordinated set of responses, which may include verbal, physiological, behavioural, and neural mechanisms. Psychotherapist Michael C. Graham describes all emotions as existing on a continuum of intensity. Thus fear might range from mild concern to terror or shame might range from simple embarrassment to toxic shame. Emotions have also been described as biologically given and a result of evolution because they provided good solutions to ancient and recurring problems that faced our ancestors. Moods are feelings that tend to be less intense than emotions and that often lack a contextual stimulus.
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The answer is:
discrete and consistent


Problem: Given the question: Extract the answer to the question from the following context. Question: Which happened later, the single-grain experiment or the discovery that the amino acid tryptophan aids the well-being of mice? Context: In the early 20th century, Carl von Voit and Max Rubner independently measured caloric energy expenditure in different species of animals, applying principles of physics in nutrition. In 1906, Edith G. Willcock and Frederick Hopkins showed that the amino acid tryptophan aids the well-being of mice but it did not assure their growth. In the middle of twelve years of attempts to isolate them, Hopkins said in a 1906 lecture that "unsuspected dietetic factors," other than calories, protein, and minerals, are needed to prevent deficiency diseases. In 1907, Stephen M. Babcock and Edwin B. Hart conducted the single-grain experiment, which took nearly four years to complete.
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The answer is:
single-grain experiment