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Popper left school at the age of 16 and attended lectures in mathematics, physics, philosophy, psychology and the history of music as a guest student at the University of Vienna. In 1919, Popper became attracted by Marxism and subsequently joined the Association of Socialist School Students. He also became a member of the Social Democratic Workers' Party of Austria, which was at that time a party that fully adopted the Marxist ideology. After the street battle in the Hörlgasse on 15 June 1919, when police shot eight of his unarmed party comrades, he became disillusioned by what he saw to be the "pseudo-scientific" historical materialism of Marx, abandoned the ideology, and remained a supporter of social liberalism throughout his life.
What party rejected Marxist ideology at the time?
A: unanswerable

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In 1998, Apple introduced its new iMac which, like the original 128K Mac, was an all-in-one computer. Its translucent plastic case, originally Bondi blue and later various additional colors, is considered an industrial design landmark of the late 1990s. The iMac did away with most of Apple's standard (and usually proprietary) connections, such as SCSI and ADB, in favor of two USB ports. It replaced a floppy disk drive with a CD-ROM drive for installing software, but was incapable of writing to CDs or other media without external third-party hardware. The iMac proved to be phenomenally successful, with 800,000 units sold in 139 days. It made the company an annual profit of US$309 million, Apple's first profitable year since Michael Spindler took over as CEO in 1995. This aesthetic was applied to the Power Macintosh and later the iBook, Apple's first consumer-level laptop computer, filling the missing quadrant of Apple's "four-square product matrix" (desktop and portable products for both consumers and professionals). More than 140,000 pre-orders were placed before it started shipping in September, and by October proved to be a large success.
How many iMac units sold in the first 193 days?
A: unanswerable

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Incandescent bulbs are much less efficient than most other types of electric lighting; incandescent bulbs convert less than 5% of the energy they use into visible light, with standard light bulbs averaging about 2.2%. The remaining energy is converted into heat. The luminous efficacy of a typical incandescent bulb is 16 lumens per watt, compared with 60 lm/W for a compact fluorescent bulb or 150 lm/W for some white LED lamps. Some applications of the incandescent bulb deliberately use the heat generated by the filament. Such applications include incubators, brooding boxes for poultry, heat lights for reptile tanks, infrared heating for industrial heating and drying processes, lava lamps, and the Easy-Bake Oven toy. Incandescent bulbs typically have short lifetimes compared with other types of lighting; around 1,000 hours for home light bulbs versus typically 10,000 hours for compact fluorescents and 30,000 hours for lighting LEDs.
How long does a typical incandescent light bulb last?
A: 1,000 hours

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The value of the deposit was obvious from the start, but the means of extracting the bitumen were not. The nearest town, Fort McMurray, Alberta was a small fur trading post, other markets were far away, and transportation costs were too high to ship the raw bituminous sand for paving. In 1915, Sidney Ells of the Federal Mines Branch experimented with separation techniques and used the bitumen to pave 600 feet of road in Edmonton, Alberta. Other roads in Alberta were paved with oil sands, but it was generally not economic. During the 1920s Dr. Karl A. Clark of the Alberta Research Council patented a hot water oil separation process and entrepreneur Robert C. Fitzsimmons built the Bitumount oil separation plant, which between 1925 and 1958 produced up to 300 barrels (50 m3) per day of bitumen using Dr. Clark's method. Most of the bitumen was used for waterproofing roofs, but other uses included fuels, lubrication oils, printers ink, medicines, rust and acid-proof paints, fireproof roofing, street paving, patent leather, and fence post preservatives. Eventually Fitzsimmons ran out of money and the plant was taken over by the Alberta government. Today the Bitumount plant is a Provincial Historic Site.
Who experimented with bitumen extraction techniques to make shipping easier?
A:
Sidney Ells