Problem: Incandescent light bulb:

The spectrum emitted by a blackbody radiator at temperatures of incandescent bulbs does not match the sensitivity characteristics of the human eye; the light emitted does not appear white, and most is not in the range of wavelengths at which the eye is most sensitive. Tungsten filaments radiate mostly infrared radiation at temperatures where they remain solid below 3,695 K (3,422 C; 6,191 F). Donald L. Klipstein explains it this way: "An ideal thermal radiator produces visible light most efficiently at temperatures around 6,300 C (6,600 K; 11,400 F). Even at this high temperature, a lot of the radiation is either infrared or ultraviolet, and the theoretical luminous efficacy (LER) is 95 lumens per watt." No known material can be used as a filament at this ideal temperature, which is hotter than the sun's surface. An upper limit for incandescent lamp luminous efficacy (LER) is around 52 lumens per watt, the theoretical value emitted by tungsten at its melting point.

At what temperature does a thermal radiator most efficiently produce light?
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A: 6,300 C

Problem: While Southeast Asia is rich in flora and fauna, Southeast Asia is facing severe deforestation which causes habitat loss for various endangered species such as orangutan and the Sumatran tiger. Predictions have been made that more than 40% of the animal and plant species in Southeast Asia could be wiped out in the 21st century. At the same time, haze has been a regular occurrence. The two worst regional hazes were in 1997 and 2006 in which multiple countries were covered with thick haze, mostly caused by "slash and burn" activities in Sumatra and Borneo. In reaction, several countries in Southeast Asia signed the ASEAN Agreement on Transboundary Haze Pollution to combat haze pollution.
How is a haze formed?
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Answer: caused by "slash and burn" activities

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
( Dejimon, branded as Digimon: Digital Monsters, stylized as DIGIMON), short for "Digital Monsters" ( Dejitaru Monsuta), is a Japanese media franchise encompassing virtual pet toys, anime, manga, video games, films and a trading card game. The franchise focuses on Digimon creatures, which are monsters living in a "Digital World", a parallel universe that originated from Earth's various communication networks. In many incarnations, Digimon are raised by humans called "Digidestined" or "Tamers", and they team up to defeat evil Digimon and human villains who are trying to destroy the fabric of the Digital world.
What term refers to the Chinese media franchise?
A: unanswerable

Context and question: Soviet Premier Nikita Khrushchev announced that a "spy-plane" had been shot down but intentionally made no reference to the pilot. As a result, the Eisenhower Administration, thinking the pilot had died in the crash, authorized the release of a cover story claiming that the plane was a "weather research aircraft" which had unintentionally strayed into Soviet airspace after the pilot had radioed "difficulties with his oxygen equipment" while flying over Turkey. The Soviets put Captain Powers on trial and displayed parts of the U-2, which had been recovered almost fully intact.
What happened to Powers in the Soviet Union?
Answer: trial

Question: During the administration of U.S. President Martin Van Buren, nearly 17,000 Cherokeesalong with approximately 2,000 black slaves owned by Cherokeeswere uprooted from their homes between 1838 and 1839 and were forced by the U.S. military to march from "emigration depots" in Eastern Tennessee (such as Fort Cass) toward the more distant Indian Territory west of Arkansas. During this relocation an estimated 4,000 Cherokees died along the way west. In the Cherokee language, the event is called Nunna daul Isunyi"the Trail Where We Cried." The Cherokees were not the only American Indians forced to emigrate as a result of the Indian removal efforts of the United States, and so the phrase "Trail of Tears" is sometimes used to refer to similar events endured by other American Indian peoples, especially among the "Five Civilized Tribes". The phrase originated as a description of the earlier emigration of the Choctaw nation.
Is there an answer to this question: Which Native American nation's emigration was first associated with the term "Trail of Tears?"

Answer: Choctaw

QUES: One of the first competitions he won was the Junior Mr. Europe contest in 1965. He won Mr. Europe the following year, at age 19. He would go on to compete in, and win, many bodybuilding contests. His bodybuilding victories included five Mr. Universe (4 NABBA [England], 1 IFBB [USA]) wins, and seven Mr. Olympia wins, a record which would stand until Lee Haney won his eighth consecutive Mr. Olympia title in 1991.

How many times did Schwarzenegger win the Mr. Olympia title?
What is the answer?
ANS:
seven