Problem: Daylight saving time:

Damage to a German steel facility occurred during a DST transition in 1993, when a computer timing system linked to a radio time synchronization signal allowed molten steel to cool for one hour less than the required duration, resulting in spattering of molten steel when it was poured. Medical devices may generate adverse events that could harm patients, without being obvious to clinicians responsible for care. These problems are compounded when the DST rules themselves change; software developers must test and perhaps modify many programs, and users must install updates and restart applications. Consumers must update devices such as programmable thermostats with the correct DST rules, or manually adjust the devices' clocks. A common strategy to resolve these problems in computer systems is to express time using the Coordinated Universal Time (UTC) rather than the local time zone. For example, Unix-based computer systems use the UTC-based Unix time internally.

What type of computer systems use an internal clock based on UTC time?
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A: Unix-based

Problem: For 2016, U.S. News & World Report ranked BYU as tied for 66th for national universities in the United States. A 2013 Quarterly Journal of Economics study of where the nation's top high school students choose to enroll ranked BYU No. 21 in its peer-reviewed study. The Princeton Review has ranked BYU the best value for college in 2007, and its library is consistently ranked in the nation's top ten No. 1 in 2004 and No. 4 in 2007. BYU is also ranked No. 19 in the U.S. News and World Report's "Great Schools, Great Prices" lineup, and No. 12 in lowest student-incurred debt. Due in part to the school's emphasis on undergraduate research, in rankings for 2008-2009, BYU was ranked No. 10 nationally for the number of students who go on to earn PhDs, No. 1 nationally for students who go on to dental school, No. 6 nationally for students who go on to law school, and No. 10 nationally for students who go on to medical school. BYU is designated as a research university with high research activity by the Carnegie Foundation for the Advancement of Teaching.]] Forbes Magazine ranked it as the No. 1 "Top University to Work For in 2014" and as the best college in Utah.
Where was BYU ranked in 2014 for number of students who go on to earn PhDs?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The developers of both Chrome and Firefox committed to developing Metro-style versions of their browsers; while Chrome's "Windows 8 mode" uses a full-screen version of the existing desktop interface, Firefox's version (which was first made available on the "Aurora" release channel in September 2013) uses a touch-optimized interface inspired by the Android version of Firefox. In October 2013, Chrome's app was changed to mimic the desktop environment used by Chrome OS. Development of the Firefox app for Windows 8 has since been cancelled, citing a lack of user adoption for the beta versions.
When was Firefox's version of Windows 9 made accesible?
A: unanswerable

Context and question: Passenger elevators capacity is related to the available floor space. Generally passenger elevators are available in capacities from 500 to 2,700 kg (1,0006,000 lb) in 230 kg (500 lb) increments.[citation needed] Generally passenger elevators in buildings of eight floors or fewer are hydraulic or electric, which can reach speeds up to 1 m/s (200 ft/min) hydraulic and up to 152 m/min (500 ft/min) electric. In buildings up to ten floors, electric and gearless elevators are likely to have speeds up to 3 m/s (500 ft/min), and above ten floors speeds range 3 to 10 m/s (5002,000 ft/min).[citation needed]
What dictates passenger elevator capacities?
Answer: the available floor space

Question: From seasons four to seven and nine, the twenty-four semi-finalists were divided by gender in order to ensure an equal gender division in the top twelve. The men and women sang separately on consecutive nights, and the bottom two in each groups were eliminated each week until only six of each remained to form the top twelve.
Is there an answer to this question: How many women were semi-finalists on season six of American Idol?

Answer: twelve

Question: Perhaps the biggest sustainability problem in Tucson, with its high desert climate, is potable water supply. The state manages all water in Arizona through its Arizona Department of Water Resources (ADWR). The primary consumer of water is Agriculture (including golf courses), which consumes about 69% of all water. Municipal (which includes residential use) accounts for about 25% of use. Energy consumption and availability is another sustainability issue. However, with over 300 days of full sun a year, Tucson has demonstrated its potential to be an ideal solar energy producer.
Is there an answer to this question: What agency manages Tucson's water?

Answer:
Arizona Department of Water Resources