Here is a question about this article: There are more than 100 freshwater fish species, varying from the giant European catfish (in the Tagus International Natural Park) to some small and endemic species that live only in small lakes (along the western portion of country, for example). Some of these rare and specific species are highly endangered because of habitat loss, pollution and drought. Up-welling along the west coast of Portugal makes the sea extremely rich in nutrients and diverse species of marine fish; the Portuguese marine waters are one of the richest in the world. Marine fish species are more common, and include thousands of species, such as the sardine (Sardina pilchardus), tuna and Atlantic mackerel. Bioluminescent species are also well represented (including species in different colour spectrum and forms), like the glowing plankton that are possible to observe in some beaches.
What is the answer to this question: How many freshwater fish species can be found in Portugal?
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So... more than 100


Here is a question about this article: While there is typically only one conceptual (or logical) and physical (or internal) view of the data, there can be any number of different external views. This allows users to see database information in a more business-related way rather than from a technical, processing viewpoint. For example, a financial department of a company needs the payment details of all employees as part of the company's expenses, but does not need details about employees that are the interest of the human resources department. Thus different departments need different views of the company's database.
What is the answer to this question: How many different external views of data are there?
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So... any number


Here is a question about this article: Von Neumann's famous 9-page paper started life as a talk at Princeton and then became a paper in Germany, which was eventually translated into English. His interest in economics that led to that paper began as follows: When lecturing at Berlin in 1928 and 1929 he spent his summers back home in Budapest, and so did the economist Nicholas Kaldor, and they hit it off. Kaldor recommended that von Neumann read a book by the mathematical economist Léon Walras. Von Neumann found some faults in that book and corrected them, for example, replacing equations by inequalities. He noticed that Walras's General Equilibrium Theory and Walras' Law, which led to systems of simultaneous linear equations, could produce the absurd result that the profit could be maximized by producing and selling a negative quantity of a product. He replaced the equations by inequalities, introduced dynamic equilibria, among other things, and eventually produced the paper.
What is the answer to this question: In who's book did von Neuman find errors in the author's equations?
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So...
Léon Walras