Problem: Anti-aircraft warfare:

Rheinmetall in Germany developed an automatic 20 mm in the 1920s and Oerlikon in Switzerland had acquired the patent to an automatic 20 mm gun designed in Germany during World War I. Germany introduced the rapid-fire 2 cm FlaK 30 and later in the decade it was redesigned by Mauser-Werke and became the 2 cm FlaK 38. Nevertheless, while 20 mm was better than a machine gun and mounted on a very small trailer made it easy to move, its effectiveness was limited. Germany therefore added a 3.7 cm. The first, the 3.7 cm FlaK 18 developed by Rheinmetall in the early 1930s, was basically an enlarged 2 cm FlaK 30. It was introduced in 1935 and production stopped the following year. A redesigned gun 3.7 cm FlaK 36 entered service in 1938, it too had a two-wheel carriage. However, by the mid-1930s the Luftwaffe realised that there was still a coverage gap between 3.7 cm and 8.8 cm guns. They started development of a 5 cm gun on a four-wheel carriage.

In the 1920s, which company developed the automatic 20 mm?
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A: Rheinmetall


Problem: The Gregorian calendar improves the approximation made by the Julian calendar by skipping three Julian leap days in every 400 years, giving an average year of 365.2425 mean solar days long. This approximation has an error of about one day per 3,300 years with respect to the mean tropical year. However, because of the precession of the equinoxes, the error with respect to the vernal equinox (which occurs, on average, 365.24237 days apart near 2000) is 1 day every 7,700 years, assuming a constant time interval between vernal equinoxes, which is not true. By any criterion, the Gregorian calendar is substantially more accurate than the 1 day in 128 years error of the Julian calendar (average year 365.25 days).
What is the approximate error for every 3,300 years?
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Answer: one day


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The Atlantic coast of the United States is low, with minor exceptions. The Appalachian Highland owes its oblique northeast-southwest trend to crustal deformations which in very early geological time gave a beginning to what later came to be the Appalachian mountain system. This system had its climax of deformation so long ago (probably in Permian time) that it has since then been very generally reduced to moderate or low relief. It owes its present-day altitude either to renewed elevations along the earlier lines or to the survival of the most resistant rocks as residual mountains. The oblique trend of this coast would be even more pronounced but for a comparatively modern crustal movement, causing a depression in the northeast resulting in an encroachment of the sea upon the land. Additionally, the southeastern section has undergone an elevation resulting in the advance of the land upon the sea.
During what geological. That the Appalachian Mountains reach their lowest point
A: unanswerable


Context and question: Approximately 12 million Africans were shipped to the Americas during the Atlantic slave trade from 1492 to 1888, with 11.5 million of those shipped to South America and the Caribbean. Brazil was the largest importer in the Americas, with 5.5 million African slaves imported, followed by the British Caribbean with 2.76 million, the Spanish Caribbean and Spanish Mainland with 1.59 million Africans, and the French Caribbean with 1.32 million. Today their descendants number approximately 150 million in South America and the Caribbean. In addition to skin color, other physical characteristics such as facial features and hair texture are often variously used in classifying peoples as black in South America and the Caribbean. In South America and the Caribbean, classification as black is also closely tied to social status and socioeconomic variables, especially in light of social conceptions of "blanqueamiento" (racial whitening) and related concepts.
How many Africans were shipped to the US between 1492 to 1888?
Answer: 12 million


Question: A high-definition remaster of the game, The Legend of Zelda: Twilight Princess HD, is being developed by Tantalus Media for the Wii U. Officially announced during a Nintendo Direct presentation on November 12, 2015, it features enhanced graphics and Amiibo functionality. The game will be released in North America and Europe on March 4, 2016; in Australia on March 5, 2016; and in Japan on March 10, 2016.
Is there an answer to this question: What kind of functionality will the remaster feature?

Answer: Amiibo


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Ship transport is an important component of Melbourne's transport system. The Port of Melbourne is Australia's largest container and general cargo port and also its busiest. The port handled two million shipping containers in a 12-month period during 2007, making it one of the top five ports in the Southern Hemisphere. Station Pier on Port Phillip Bay is the main passenger ship terminal with cruise ships and the Spirit of Tasmania ferries which cross Bass Strait to Tasmania docking there. Ferries and water taxis run from berths along the Yarra River as far upstream as South Yarra and across Port Phillip Bay.
How many shipping containers did the Port of Melbourne handle during a 12-month period in 2007, making it one of the top five ports in the Southern Hemisphere?
A:
two million