Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In the late 1980s, key breakthroughs in GaN epitaxial growth and p-type doping ushered in the modern era of GaN-based optoelectronic devices. Building upon this foundation, Dr. Moustakas at Boston University patented a method for producing high-brightness blue LEDs using a new two-step process. Two years later, in 1993, high-brightness blue LEDs were demonstrated again by Shuji Nakamura of Nichia Corporation using a gallium nitride growth process similar to Dr. Moustakas's. Both Dr. Moustakas and Mr. Nakamura were issued separate patents, which confused the issue of who was the original inventor (partly because although Dr. Moustakas invented his first, Dr. Nakamura filed first).[citation needed] This new development revolutionized LED lighting, making high-power blue light sources practical, leading to the development of technologies like BlueRay, as well as allowing the bright high resolution screens of modern tablets and phones.[citation needed]
What technology was made possible by low-power blue light sources?
A: unanswerable

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Studies by Nathaniel Kleitman in 1938 and by Derk-Jan Dijk and Charles Czeisler in the 1990s put human subjects on enforced 28-hour sleepwake cycles, in constant dim light and with other time cues suppressed, for over a month. Because normal people cannot entrain to a 28-hour day in dim light if at all,[citation needed] this is referred to as a forced desynchrony protocol. Sleep and wake episodes are uncoupled from the endogenous circadian period of about 24.18 hours and researchers are allowed to assess the effects of circadian phase on aspects of sleep and wakefulness including sleep latency and other functions.[page needed]
How long did the suppression of time clues study last?
A: month

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In the aftermath of the 1986 U.S. attack, the army was purged of perceived disloyal elements, and in 1988, Gaddafi announced the creation of a popular militia to replace the army and police. In 1987, Libya began production of mustard gas at a facility in Rabta, although publicly denying it was stockpiling chemical weapons, and unsuccessfully attempted to develop nuclear weapons. The period also saw a growth in domestic Islamist opposition, formulated into groups like the Muslim Brotherhood and the Libyan Islamic Fighting Group. A number of assassination attempts against Gaddafi were foiled, and in turn, 1989 saw the security forces raid mosques believed to be centres of counter-revolutionary preaching. In October 1993, elements of the increasingly marginalised army initiated a failed coup in Misrata, while in September 1995, Islamists launched an insurgency in Benghazi, and in July 1996 an anti-Gaddafist football riot broke out in Tripoli. The Revolutionary Committees experienced a resurgence to combat these Islamists.
What chemical weapon did Libya start making in 1987?
A: mustard gas

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Each play constitutes a down. The offence must advance the ball at least ten yards towards the opponents' goal line within three downs or forfeit the ball to their opponents. Once ten yards have been gained the offence gains a new set of three downs (rather than the four downs given in American football). Downs do not accumulate. If the offensive team completes 10 yards on their first play, they lose the other two downs and are granted another set of three. If a team fails to gain ten yards in two downs they usually punt the ball on third down or try to kick a field goal (see below), depending on their position on the field. The team may, however use its third down in an attempt to advance the ball and gain a cumulative 10 yards.
What does a team do in their position on the field when they haven't advanced the ball enough to score?
A:
unanswerable