Problem: Electric motor:

Stepper motors are a type of motor frequently used when precise rotations are required. In a stepper motor an internal rotor containing PMs or a magnetically soft rotor with salient poles is controlled by a set of external magnets that are switched electronically. A stepper motor may also be thought of as a cross between a DC electric motor and a rotary solenoid. As each coil is energized in turn, the rotor aligns itself with the magnetic field produced by the energized field winding. Unlike a synchronous motor, in its application, the stepper motor may not rotate continuously; instead, it "steps"starts and then quickly stops againfrom one position to the next as field windings are energized and de-energized in sequence. Depending on the sequence, the rotor may turn forwards or backwards, and it may change direction, stop, speed up or slow down arbitrarily at any time.

When are stepper motors least useful?
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A: unanswerable

Problem: On the Origin of Species:

In the United States, botanist Asa Gray an American colleague of Darwin negotiated with a Boston publisher for publication of an authorised American version, but learnt that two New York publishing firms were already planning to exploit the absence of international copyright to print Origin. Darwin was delighted by the popularity of the book, and asked Gray to keep any profits. Gray managed to negotiate a 5% royalty with Appleton's of New York, who got their edition out in mid January 1860, and the other two withdrew. In a May letter, Darwin mentioned a print run of 2,500 copies, but it is not clear if this referred to the first printing only as there were four that year.

What was the print run that Darwin mentioned for On the Origin of Species?
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A: 2,500 copies

Problem: Vacuum:

Vacuum is space void of matter. The word stems from the Latin adjective vacuus for "vacant" or "void". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressure. Physicists often discuss ideal test results that would occur in a perfect vacuum, which they sometimes simply call "vacuum" or free space, and use the term partial vacuum to refer to an actual imperfect vacuum as one might have in a laboratory or in space. In engineering and applied physics on the other hand, vacuum refers to any space in which the pressure is lower than atmospheric pressure. The Latin term in vacuo is used to describe an object as being in what would otherwise be a vacuum.

What does the term used by Physicists, partial vacuum, refer to?
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A: imperfect vacuum

Problem: Affirmative action in the United States:

In the year 2000, according to a study by American Association of University Professors (AAUP), affirmative action promoted diversity within colleges and universities. This has been shown to have positive effects on the educational outcomes and experiences of college students as well as the teaching of faculty members. According to a study by Geoffrey Maruyama and Jose F. Moreno, the results showed that faculty members believed diversity helps students to reach the essential goals of a college education, Caucasian students suffer no detrimental effects from classroom diversity, and that attention to multicultural learning improves the ability of colleges and universities to accomplish their missions. Furthermore, a diverse population of students offers unique perspectives in order to challenge preconceived notions through exposure to the experiences and ideas of others. According to Professor Gurin of the University of Michigan, skills such as "perspective-taking, acceptance of differences, a willingness and capacity to find commonalities among differences, acceptance of conflict as normal, conflict resolution, participation in democracy, and interest in the wider social world" can potentially be developed in college while being exposed to heterogeneous group of students. In addition, broadening perspectives helps students confront personal and substantive stereotypes and fosters discussion about racial and ethnic issues in a classroom setting. Furthermore, the 2000 AAUP study states that having a diversity of views leads to a better discussion and greater understanding among the students on issues of race, tolerance, fairness, etc.

Who supposedly suffers a lot of detrimental effects from classroom diversity?
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A:
unanswerable