Problem: Annelid:

Annelids with blood vessels use metanephridia to remove soluble waste products, while those without use protonephridia. Both of these systems use a two-stage filtration process, in which fluid and waste products are first extracted and these are filtered again to re-absorb any re-usable materials while dumping toxic and spent materials as urine. The difference is that protonephridia combine both filtration stages in the same organ, while metanephridia perform only the second filtration and rely on other mechanisms for the first – in annelids special filter cells in the walls of the blood vessels let fluids and other small molecules pass into the coelomic fluid, where it circulates to the metanephridia. In annelids the points at which fluid enters the protonephridia or metanephridia are on the forward side of a septum while the second-stage filter and the nephridiopore (exit opening in the body wall) are in the following segment. As a result, the hindmost segment (before the growth zone and pygidium) has no structure that extracts its wastes, as there is no following segment to filter and discharge them, while the first segment contains an extraction structure that passes wastes to the second, but does not contain the structures that re-filter and discharge urine.

What annelid system combines both filtration states in eight organs?
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A: unanswerable


Problem: Melbourne:

A brash boosterism that had typified Melbourne during this time ended in the early 1890s with a severe depression of the city's economy, sending the local finance and property industries into a period of chaos during which 16 small "land banks" and building societies collapsed, and 133 limited companies went into liquidation. The Melbourne financial crisis was a contributing factor in the Australian economic depression of the 1890s and the Australian banking crisis of 1893. The effects of the depression on the city were profound, with virtually no new construction until the late 1890s.

During what decade did Melbourne suffer a sever economic depression?
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A: early 1890s


Problem: Education:

As an academic field, philosophy of education is "the philosophical study of education and its problems (...) its central subject matter is education, and its methods are those of philosophy". "The philosophy of education may be either the philosophy of the process of education or the philosophy of the discipline of education. That is, it may be part of the discipline in the sense of being concerned with the aims, forms, methods, or results of the process of educating or being educated; or it may be metadisciplinary in the sense of being concerned with the concepts, aims, and methods of the discipline." As such, it is both part of the field of education and a field of applied philosophy, drawing from fields of metaphysics, epistemology, axiology and the philosophical approaches (speculative, prescriptive, and/or analytic) to address questions in and about pedagogy, education policy, and curriculum, as well as the process of learning, to name a few. For example, it might study what constitutes upbringing and education, the values and norms revealed through upbringing and educational practices, the limits and legitimization of education as an academic discipline, and the relation between education theory and practice.

What does not draw from fields of metaphysics? 
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A: unanswerable


Problem: Late Middle Ages:

This new approach liberated scientific speculation from the dogmatic restraints of Aristotelian science, and paved the way for new approaches. Particularly within the field of theories of motion great advances were made, when such scholars as Jean Buridan, Nicole Oresme and the Oxford Calculators challenged the work of Aristotle. Buridan developed the theory of impetus as the cause of the motion of projectiles, which was an important step towards the modern concept of inertia. The works of these scholars anticipated the heliocentric worldview of Nicolaus Copernicus.

Which scholars made great advances in the theories of motion?
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A:
Jean Buridan, Nicole Oresme and the Oxford Calculators