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In Canada, the term "football" may refer to Canadian football and American football collectively, or to either sport specifically, depending on context. The two sports have shared origins and are closely related but have significant differences. In particular, Canadian football has 12 players on the field per team rather than 11; the field is roughly 10 yards wider, and 10 yards longer between end-zones that are themselves 10 yards deeper; and a team has only three downs to gain 10 yards, which results in less offensive rushing than in the American game. In the Canadian game all players on the defending team, when a down begins, must be at least 1 yard from the line of scrimmage. (The American game has a similar "neutral zone" but it is only the length of the football.)
Which version of North American football has a smaller football?
A: unanswerable

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Earth was initially molten due to extreme volcanism and frequent collisions with other bodies. Eventually, the outer layer of the planet cooled to form a solid crust when water began accumulating in the atmosphere. The Moon formed soon afterwards, possibly as the result of a Mars-sized object with about 10% of the Earth's mass impacting the planet in a glancing blow. Some of this object's mass merged with the Earth, significantly altering its internal composition, and a portion was ejected into space. Some of the material survived to form an orbiting moon. Outgassing and volcanic activity produced the primordial atmosphere. Condensing water vapor, augmented by ice delivered from comets, produced the oceans.
When water was creating the oceans what was happening to atmospheric water vapor?
A: Condensing

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King Matthias Corvinus of Hungary (14581490) was one of the most prominent figures of the period, directing campaigns to the West, conquering Bohemia in answer to the Pope's call for help against the Hussite Protestants. Also, in resolving political hostilities with the German emperor Frederick III of Habsburg, he invaded his western domains. Matthew organized the Black Army of mercenary soldiers; it was considered as the biggest army of its time. Using this powerful tool, the Hungarian king led wars against the Turkish armies and stopped the Ottomans during his reign. After the death of Matthew, and with end of the Black Army, the Ottoman Empire grew in strength and Central Europe was defenseless. At the Battle of Mohacs, the forces of the Ottoman Empire annihilated the Hungarian army and Louis II of Hungary drowned in the Csele Creek while trying to escape. The leader of the Hungarian army, Pal Tomori, also died in the battle. This is considered to be one of the final battles of Medieval times.
Who did Matthias lose to conquer Bohemia?
A: unanswerable

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Vacuum is useful in a variety of processes and devices. Its first widespread use was in the incandescent light bulb to protect the filament from chemical degradation. The chemical inertness produced by a vacuum is also useful for electron beam welding, cold welding, vacuum packing and vacuum frying. Ultra-high vacuum is used in the study of atomically clean substrates, as only a very good vacuum preserves atomic-scale clean surfaces for a reasonably long time (on the order of minutes to days). High to ultra-high vacuum removes the obstruction of air, allowing particle beams to deposit or remove materials without contamination. This is the principle behind chemical vapor deposition, physical vapor deposition, and dry etching which are essential to the fabrication of semiconductors and optical coatings, and to surface science. The reduction of convection provides the thermal insulation of thermos bottles. Deep vacuum lowers the boiling point of liquids and promotes low temperature outgassing which is used in freeze drying, adhesive preparation, distillation, metallurgy, and process purging. The electrical properties of vacuum make electron microscopes and vacuum tubes possible, including cathode ray tubes. The elimination of air friction is useful for flywheel energy storage and ultracentrifuges.
How does freeze drying, distillation and metallurgy benefit from a deep vacuum?
A:
Deep vacuum lowers the boiling point of liquids and promotes low temperature outgassing