Input: Read this: On the morning of 11 September 2001, 19 men affiliated with al-Qaeda hijacked four airliners all bound for California. Once the hijackers assumed control of the airliners, they told the passengers that they had the bomb on board and would spare the lives of passengers and crew once their demands were met – no passenger and crew actually suspected that they would use the airliners as suicide weapons since it had never happened before in history. The hijackers – members of al-Qaeda's Hamburg cell – intentionally crashed two airliners into the Twin Towers of the World Trade Center in New York City. Both buildings collapsed within two hours from fire damage related to the crashes, destroying nearby buildings and damaging others. The hijackers crashed a third airliner into the Pentagon in Arlington County, Virginia, just outside Washington D.C. The fourth plane crashed into a field near Shanksville, Pennsylvania, after some of its passengers and flight crew attempted to retake control of the plane, which the hijackers had redirected toward Washington D.C., to target the White House, or the U.S. Capitol. No flights had survivors. A total of 2,977 victims and the 19 hijackers perished in the attacks.
Question: How many passengers died?

Output: unanswerable


Input: Read this: Infrared vibrational spectroscopy (see also near-infrared spectroscopy) is a technique that can be used to identify molecules by analysis of their constituent bonds. Each chemical bond in a molecule vibrates at a frequency characteristic of that bond. A group of atoms in a molecule (e.g., CH2) may have multiple modes of oscillation caused by the stretching and bending motions of the group as a whole. If an oscillation leads to a change in dipole in the molecule then it will absorb a photon that has the same frequency. The vibrational frequencies of most molecules correspond to the frequencies of infrared light. Typically, the technique is used to study organic compounds using light radiation from 4000–400 cm−1, the mid-infrared. A spectrum of all the frequencies of absorption in a sample is recorded. This can be used to gain information about the sample composition in terms of chemical groups present and also its purity (for example, a wet sample will show a broad O-H absorption around 3200 cm−1).
Question: What do most vibrations correspond to the frequencies of?

Output: unanswerable


Input: Read this: The modern literary language is usually considered to date from the time of Alexander Pushkin (Алекса́ндр Пу́шкин) in the first third of the 19th century. Pushkin revolutionized Russian literature by rejecting archaic grammar and vocabulary (so-called "высо́кий стиль" — "high style") in favor of grammar and vocabulary found in the spoken language of the time. Even modern readers of younger age may only experience slight difficulties understanding some words in Pushkin's texts, since relatively few words used by Pushkin have become archaic or changed meaning. In fact, many expressions used by Russian writers of the early 19th century, in particular Pushkin, Mikhail Lermontov (Михаи́л Ле́рмонтов), Nikolai Gogol (Никола́й Го́голь), Aleksander Griboyedov (Алекса́ндр Грибое́дов), became proverbs or sayings which can be frequently found even in modern Russian colloquial speech.
Question: How many words used by Lermontov have become archaic?

Output: unanswerable


Input: Read this: The origins of the department store lay in the growth of the conspicuous consumer society at the turn of the 19th century. As the Industrial Revolution accelerated economy expansion, the affluent middle-class grew in size and wealth. This urbanized social group, sharing a culture of consumption and changing fashion, was the catalyst for the retail revolution. As rising prosperity and social mobility increased the number of people, especially women (who found they could shop unaccompanied at department stores without damaging their reputation), with disposable income in the late Georgian period, window shopping was transformed into a leisure activity and entrepreneurs, like the potter Josiah Wedgwood, pioneered the use of marketing techniques to influence the prevailing tastes and preferences of society.
Question: When didn't the idea of a "consumer society" begin? 

Output:
unanswerable