Input: Article: The Scheinergrade (Sch.) system was devised by the German astronomer Julius Scheiner (18581913) 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.

Now answer this question: What is the Scheinergrade system used for?

Output: comparing the speeds of plates used for astronomical photography

Article: By the 20th century, Philadelphia had become known as "corrupt and contented", with a complacent population and an entrenched Republican political machine. The first major reform came in 1917 when outrage over the election-year murder of a police officer led to the shrinking of the Philadelphia City Council from two houses to just one. In July 1919, Philadelphia was one of more than 36 industrial cities nationally to suffer a race riot of ethnic whites against blacks during Red Summer, in post-World War I unrest, as recent immigrants competed with blacks for jobs. In the 1920s, the public flouting of Prohibition laws, mob violence, and police involvement in illegal activities led to the appointment of Brigadier General Smedley Butler of the U.S. Marine Corps as director of public safety, but political pressure prevented any long-term success in fighting crime and corruption.

Question: What phrase could describe Philadelphia of the early 20th century?
Ans: corrupt and contented

Here is a question about this article: As another example, she points to work by Thomas et al., who sought to distinguish between the Y chromosomes of Jewish priests (Kohanim), (in Judaism, membership in the priesthood is passed on through the father's line) and the Y chromosomes of non-Jews. Abu el-Haj concluded that this new "race science" calls attention to the importance of "ancestry" (narrowly defined, as it does not include all ancestors) in some religions and in popular culture, and people's desire to use science to confirm their claims about ancestry; this "race science", she argues, is fundamentally different from older notions of race that were used to explain differences in human behaviour or social status:
What is the answer to this question: What do people desire to use science to confirm?
****
So... their claims about ancestry

The problem: Answer a question about this article:
The 1998 edition of Guinness Book of World Records stated: "No female artist has sold more records than Madonna around the world". In 1999 Madonna signed to play a violin teacher in the film Music of the Heart but left the project, citing "creative differences" with director Wes Craven. She recorded the single "Beautiful Stranger" for the 1999 film Austin Powers: The Spy Who Shagged Me. It reached number 19 on the Hot 100 solely on radio airplay. Madonna won a Grammy Award for "Best Song Written for a Motion Picture, Television or Other Visual Media".
Who was the director of Music of the Heart?
****
The answer: Wes Craven

Problem: Please answer a question about the following article about Spectre (2015 film):
To promote the film, production continued the trend established during Skyfall's production of releasing still images of clapperboards and video blogs on Eon's official social media accounts.
For what film did Eon first use this method of promotion?
A: Skyfall

Question: Read this and answer the question

Ottoman government deliberately pursued a policy for the development of Bursa, Edirne, and Istanbul, successive Ottoman capitals, into major commercial and industrial centres, considering that merchants and artisans were indispensable in creating a new metropolis. To this end, Mehmed and his successor Bayezid, also encouraged and welcomed migration of the Jews from different parts of Europe, who were settled in Istanbul and other port cities like Salonica. In many places in Europe, Jews were suffering persecution at the hands of their Christian counterparts, such as in Spain after the conclusion of Reconquista. The tolerance displayed by the Turks was welcomed by the immigrants.

Persecution of Jews in Spain occurred after what event concluded?
Answer:
the conclusion of Reconquista