Article: The Scheinergrade (Sch.) system was devised by the German astronomer Julius Scheiner (1858–1913) in 1894 originally as a method of comparing the speeds of plates used for astronomical photography. Scheiner's system rated the speed of a plate by the least exposure to produce a visible darkening upon development. Speed was expressed in degrees Scheiner, originally ranging from 1° Sch. to 20° Sch., where an increment of 19° Sch. corresponded to a hundredfold increase in sensitivity, which meant that an increment of 3° Sch. came close to a doubling of sensitivity.

Question: What do degrees Scheiner indicate?
Ans: the speed of a plate


Article: Richmond is home to the rapidly developing Virginia BioTechnology Research Park, which opened in 1995 as an incubator facility for biotechnology and pharmaceutical companies. Located adjacent to the Medical College of Virginia (MCV) Campus of Virginia Commonwealth University, the park currently[when?] has more than 575,000 square feet (53,400 m2) of research, laboratory and office space for a diverse tenant mix of companies, research institutes, government laboratories and non-profit organizations. The United Network for Organ Sharing, which maintains the nation's organ transplant waiting list, occupies one building in the park. Philip Morris USA opened a $350 million research and development facility in the park in 2007. Once fully developed, park officials expect the site to employ roughly 3,000 scientists, technicians and engineers.

Question: How many square meters of space does Virginia BioTechnology Research Park consist of?
Ans: 53,400


Article: The Grito de Dolores ("Cry of Dolores") also known as El Grito de la Independencia ("Cry of Independence"), uttered from the small town of Dolores near Guanajuato on September 16, 1810, is the event that marks the beginning of the Mexican War of Independence and is the most important national holiday observed in Mexico. The "Grito" was the battle cry of the Mexican War of Independence by Miguel Hidalgo y Costilla, a Roman Catholic priest. Hidalgo and several criollos were involved in a planned revolt against the Spanish colonial government, and the plotters were betrayed. Fearing his arrest, Hidalgo commanded his brother Mauricio as well as Ignacio Allende and Mariano Abasolo to go with a number of other armed men to make the sheriff release the pro-independence inmates there on the night of September 15. They managed to set eighty free. Around 6:00 am September 16, 1810, Hidalgo ordered the church bells to be rung and gathered his congregation. Flanked by Allende and Juan Aldama, he addressed the people in front of his church, encouraging them to revolt. The Battle of Guanajuato, the first major engagement of the insurgency, occurred four days later. Mexico's independence from Spain was effectively declared in the Declaration of Independence of the Mexican Empire on September 27, 1821, after a decade of war. Unrest followed for the next several decades, as different factions fought for control of Mexico.

Question: What was the battle cry of the war?
Ans: Grito


Article: Brass, which is an alloy of copper and zinc, has been used since at least the 10th century BC in Judea and by the 7th century BC in Ancient Greece. Zinc metal was not produced on a large scale until the 12th century in India and was unknown to Europe until the end of the 16th century. The mines of Rajasthan have given definite evidence of zinc production going back to the 6th century BC. To date, the oldest evidence of pure zinc comes from Zawar, in Rajasthan, as early as the 9th century AD when a distillation process was employed to make pure zinc. Alchemists burned zinc in air to form what they called "philosopher's wool" or "white snow".

Question: Brass is an alloy of what two elements?
Ans:
copper and zinc