Problem: Vacuum:

Stars, planets, and moons keep their atmospheres by gravitational attraction, and as such, atmospheres have no clearly delineated boundary: the density of atmospheric gas simply decreases with distance from the object. The Earth's atmospheric pressure drops to about 6998320000000000000♠3.2×10−2 Pa at 100 kilometres (62 mi) of altitude, the Kármán line, which is a common definition of the boundary with outer space. Beyond this line, isotropic gas pressure rapidly becomes insignificant when compared to radiation pressure from the Sun and the dynamic pressure of the solar winds, so the definition of pressure becomes difficult to interpret. The thermosphere in this range has large gradients of pressure, temperature and composition, and varies greatly due to space weather. Astrophysicists prefer to use number density to describe these environments, in units of particles per cubic centimetre.

What does the Sun's atmospheric pressure drop to at 100 km of altitude?
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A: unanswerable


Problem: Wood:

Knots do not necessarily influence the stiffness of structural timber, this will depend on the size and location. Stiffness and elastic strength are more dependent upon the sound wood than upon localized defects. The breaking strength is very susceptible to defects. Sound knots do not weaken wood when subject to compression parallel to the grain.

What is wood's breaking strength susceptible to? 
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A: defects


Problem: Catalan language:

According to Ethnologue, the lexical similarity between Catalan and other Romance languages is: 87% with Italian; 85% with Portuguese; 80% with Spanish; 76% with Ladin; 75% with Sardinian; and 73% with Romanian.

Hoe similar is Catalan to Portuguese?
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A: 85%


Problem: Brigham Young University:

In 1903, Brigham Young Academy was dissolved, and was replaced by two institutions: Brigham Young High School, and Brigham Young University. (The BY High School class of 1907 was ultimately responsible for the famous giant "Y" that is to this day embedded on a mountain near campus.) The Board elected George H. Brimhall as the new President of BYU. He had not received a high school education until he was forty. Nevertheless, he was an excellent orator and organizer. Under his tenure in 1904 the new Brigham Young University bought 17 acres (69,000 m2) of land from Provo called "Temple Hill". After some controversy among locals over BYU's purchase of this property, construction began in 1909 on the first building on the current campus, the Karl G. Maeser Memorial. Brimhall also presided over the University during a brief crisis involving the theory of evolution. The religious nature of the school seemed at the time to collide with this scientific theory. Joseph F. Smith, LDS Church president, settled the question for a time by asking that evolution not be taught at the school. A few have described the school at this time as nothing more than a "religious seminary". However, many of its graduates at this time would go on to great success and become well renowned in their fields.

At what age did BYU's elected president in 1904, George H. Brimhall, receive his high school education?
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A:
forty