Problem: Royal Dutch Shell:

Over the course of 2013, the corporation began the sale of its US shale gas assets and cancelled a US$20 billion gas project that was to be constructed in the US state of Louisiana. A new CEO Ben van Beurden was appointed in January 2014, prior to the announcement that the corporation's overall performance in 2013 was 38 per cent lower than 2012the value of Shell's shares fell by 3 per cent as a result. Following the sale of the majority of its Australian assets in February 2014, the corporation plans to sell a further US$15 billion worth of assets in the period leading up to 2015, with deals announced in Australia, Brazil and Italy.

Who was the CEO in 2013?
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A: unanswerable

Problem: During his annual state-of-the-nation address on September 2, 2014, President of Mexico Enrique Pena Nieto unveiled plans for a new international airport to ease the city's notorious air traffic congestion, tentatively slated for a 2018 opening. The new airport, which would have six runways, will cost $9.15 billion and would be built on vacant federal land east of Mexico City International Airport. Goals are to eventually handle 120 million passengers a year, which would make it the busiest airport in the world.
How much does the new airport cost?
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Answer: $9.15 billion

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Stepper motors can be rotated to a specific angle in discrete steps with ease, and hence stepper motors are used for read/write head positioning in computer floppy diskette drives. They were used for the same purpose in pre-gigabyte era computer disk drives, where the precision and speed they offered was adequate for the correct positioning of the read/write head of a hard disk drive. As drive density increased, the precision and speed limitations of stepper motors made them obsolete for hard drivesthe precision limitation made them unusable, and the speed limitation made them uncompetitivethus newer hard disk drives use voice coil-based head actuator systems. (The term "voice coil" in this connection is historic; it refers to the structure in a typical (cone type) loudspeaker. This structure was used for a while to position the heads. Modern drives have a pivoted coil mount; the coil swings back and forth, something like a blade of a rotating fan. Nevertheless, like a voice coil, modern actuator coil conductors (the magnet wire) move perpendicular to the magnetic lines of force.)
What do newer computer drives use instead of stepper motors?
A: voice coil-based head actuator systems

Context and question: Green and the CPI further noted another exploit of the ESA in their discussion of the critically endangered cotton-top tamarin (Saguinus oedipus). Not only had they found documentation that 151 of these primates had inadvertently made their way from the Harvard-affiliated New England Regional Primate Research Center into the exotic pet trade through the aforementioned loophole, but in October 1976, over 800 cotton-top tamarins were imported into the United States in order to beat the official listing of the species under the ESA.
What school was running the pet trade?
Answer: unanswerable

Question: Evidence of wheeled vehicles appeared in the mid 4th millennium BC, near-simultaneously in Mesopotamia, the Northern Caucasus (Maykop culture) and Central Europe. The wheel initially took the form of the potter's wheel. The new concept quickly led to wheeled vehicles and mill wheels. The Sumerians' cuneiform writing system is the oldest (or second oldest after the Egyptian hieroglyphs) which has been deciphered (the status of even older inscriptions such as the Jiahu symbols and Tartaria tablets is controversial). The Sumerians were among the first astronomers, mapping the stars into sets of constellations, many of which survived in the zodiac and were also recognized by the ancient Greeks. They were also aware of the five planets that are easily visible to the naked eye.
Is there an answer to this question: How many planets were the Sumerians aware of?

Answer: five

Problem: General Electric:

In 1983, New York State Attorney General Robert Abrams filed suit in the United States District Court for the Northern District of New York to compel GE to pay for the cleanup of what was claimed to be more than 100,000 tons of chemicals dumped from their plant in Waterford, New York. In 1999, the company agreed to pay a $250 million settlement in connection with claims it polluted the Housatonic River (Pittsfield, Massachusetts) and other sites with polychlorinated biphenyls (PCBs) and other hazardous substances.

What was the location of the pollution caused by GE in the Housatonic River?
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A:
Pittsfield, Massachusetts