Input: Read this: The lateral cut NAB curve was remarkably similar to the NBC Orthacoustic curve that evolved from practices within the National Broadcasting Company since the mid-1930s. Empirically, and not by any formula, it was learned that the bass end of the audio spectrum below 100 Hz could be boosted somewhat to override system hum and turntable rumble noises. Likewise at the treble end beginning at 1,000 Hz, if audio frequencies were boosted by 16 dB at 10,000 Hz the delicate sibilant sounds of speech and high overtones of musical instruments could survive the noise level of cellulose acetate, lacquer/aluminum, and vinyl disc media. When the record was played back using a complementary inverse curve, signal-to-noise ratio was improved and the programming sounded more lifelike.
Question: What helped cause the most life like sound?

Output: using a complementary inverse curve

Input: Read this: Philadelphia once comprised six congressional districts. However, as a result of the city's declining population, it now has only four: the 1st district, represented by Bob Brady; the 2nd, represented by Chaka Fattah; the 8th, represented by Mike Fitzpatrick; and the 13th, represented by Brendan Boyle. All but Fitzpatrick are Democrats. Although they are usually swamped by Democrats in city, state and national elections, Republicans still have some support in the area, primarily in the northeast. A Republican represented a significant portion of Philadelphia in the House as late as 1983, and Sam Katz ran competitive mayoral races as the Republican nominee in both 1999 and 2003.
Question: How many congressional districts were there at the peak population?

Output: six

Input: Read this: Midway through the 19th century, the focus of geology shifted from description and classification to attempts to understand how the surface of the Earth had changed. The first comprehensive theories of mountain building were proposed during this period, as were the first modern theories of earthquakes and volcanoes. Louis Agassiz and others established the reality of continent-covering ice ages, and "fluvialists" like Andrew Crombie Ramsay argued that river valleys were formed, over millions of years by the rivers that flow through them. After the discovery of radioactivity, radiometric dating methods were developed, starting in the 20th century. Alfred Wegener's theory of "continental drift" was widely dismissed when he proposed it in the 1910s, but new data gathered in the 1950s and 1960s led to the theory of plate tectonics, which provided a plausible mechanism for it. Plate tectonics also provided a unified explanation for a wide range of seemingly unrelated geological phenomena. Since 1970 it has served as the unifying principle in geology.
Question: What changed about the way geology was implemented during the 19th century?

Output: shifted from description and classification to attempts to understand how the surface of the Earth had changed

Input: Read this: Nociceptive pain is caused by stimulation of peripheral nerve fibers that respond to stimuli approaching or exceeding harmful intensity (nociceptors), and may be classified according to the mode of noxious stimulation. The most common categories are "thermal" (e.g. heat or cold), "mechanical" (e.g. crushing, tearing, shearing, etc.) and "chemical" (e.g. iodine in a cut or chemicals released during inflammation). Some nociceptors respond to more than one of these modalities and are consequently designated polymodal.
Question: What type of pain is caused by stimulation of fiber?

Output:
unanswerable