The problem: Answer a question about this article:
Albert Einstein proposed that the laws of physics should be based on the principle of relativity. This principle holds that the rules of physics must be the same for all observers, regardless of the frame of reference that is used, and that light propagates at the same speed in all reference frames. This theory was motivated by Maxwell's equations, which show that electromagnetic waves propagate in a vacuum at the speed of light. However, Maxwell's equations give no indication of what this speed is relative to. Prior to Einstein, it was thought that this speed was relative to a fixed medium, called the luminiferous ether. In contrast, the theory of special relativity postulates that light propagates at the speed of light in all inertial frames, and examines the implications of this postulate.
lbert Einstein proposed that the laws of physics should be based on what principle?
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The answer: relativity


Problem: Please answer a question about the following article about IPod:
The iTunes Store (introduced April 29, 2003) is an online media store run by Apple and accessed through iTunes. The store became the market leader soon after its launch and Apple announced the sale of videos through the store on October 12, 2005. Full-length movies became available on September 12, 2006.
In what year did videos first become available on iTunes?
A: 2005


Question: Read this and answer the question

Elizabeth and Philip were married on 20 November 1947 at Westminster Abbey. They received 2500 wedding gifts from around the world. Because Britain had not yet completely recovered from the devastation of the war, Elizabeth required ration coupons to buy the material for her gown, which was designed by Norman Hartnell. In post-war Britain, it was not acceptable for the Duke of Edinburgh's German relations, including his three surviving sisters, to be invited to the wedding. The Duke of Windsor, formerly King Edward VIII, was not invited either.

At what famous cathedral was Elizabeth married?
Answer: Westminster Abbey


Problem: To the southwest, the principality of Halych had developed trade relations with its Polish, Hungarian and Lithuanian neighbours and emerged as the local successor to Kievan Rus'. In 1199, Prince Roman Mstislavich united the two previously separate principalities. In 1202 he conquered Kiev, and assumed the title of Grand Duke of Kievan Rus', which was held by the rulers of Vladimir-Suzdal since 1169. His son, Prince Daniil (r. 1238–1264) looked for support from the West. He accepted a crown as a "Rex Rusiae" ("King of Russia") from the Roman papacy, apparently doing so without breaking with Constantinople. In 1370, the patriarch of the Eastern Orthodox Church in Constantinople granted the King of Poland a metropolitan for his Russian subjects. Lithuanian rulers also requested and received a metropolitan for Novagrudok shortly afterwards. Cyprian, a candidate pushed by the Lithuanian rulers, became Metropolitan of Kiev in 1375 and metropolitan of Moscow in 1382; this way the church in the Russian countries was reunited for some time. In 1439, Kiev became the seat of a separate "Metropolitan of Kiev, Galich and all Rus'" for all Greek Orthodox Christians under Polish-Lithuanian rule.
In what year did Mstislavich defeat the Kiev?
The answer is the following: 1202


Throughout the course of its life, a number of peripherals were released which added to the functionality of the SNES. Many of these devices were modeled after earlier add-ons for the NES: the Super Scope is a light gun functionally similar to the NES Zapper (though the Super Scope features wireless capabilities) and the Super Advantage is an arcade-style joystick with adjustable turbo settings akin to the NES Advantage. Nintendo also released the SNES Mouse in conjunction with its Mario Paint title. Hudson Soft, under license from Nintendo, released the Super Multitap, a multiplayer adapter for use with its popular series of Bomberman games. Some of the more unusual controllers include the BatterUP baseball bat, the Life Fitness Entertainment System (an exercise bike controller with built-in monitoring software), and the TeeV Golf golf club.
What game came with a baseball bat controller?
BatterUP


Here is a question about this article: The large magnitude of solar energy available makes it a highly appealing source of electricity. The United Nations Development Programme in its 2000 World Energy Assessment found that the annual potential of solar energy was 1,575–49,837 exajoules (EJ). This is several times larger than the total world energy consumption, which was 559.8 EJ in 2012.
What is the answer to this question: What is solar energy's yearly potential?
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So...
1,575–49,837 exajoules (EJ)