Problem: Antenna (radio):

Polarization is predictable from an antenna's geometry, although in some cases it is not at all obvious (such as for the quad antenna). An antenna's linear polarization is generally along the direction (as viewed from the receiving location) of the antenna's currents when such a direction can be defined. For instance, a vertical whip antenna or Wi-Fi antenna vertically oriented will transmit and receive in the vertical polarization. Antennas with horizontal elements, such as most rooftop TV antennas in the United States, are horizontally polarized (broadcast TV in the U.S. usually uses horizontal polarization). Even when the antenna system has a vertical orientation, such as an array of horizontal dipole antennas, the polarization is in the horizontal direction corresponding to the current flow. The polarization of a commercial antenna is an essential specification.

The polarization of what antenna is essential specification?
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A: commercial antenna


Problem: Dialect:

In the early 20th century, the vast conscription of Italian men from all throughout Italy during World War I is credited with facilitating the diffusion of standard Italian among less educated Italian men, as these men from various regions with various regional languages were forced to communicate with each other in a common tongue while serving in the Italian military. With the eventual spread of the radio and television throughout Italy and the establishment of public education, Italians from all regions were increasingly exposed to standard Italian, while literacy rates among all social classes improved. Today, the majority of Italians are able to speak standard Italian, though many Italians still speak their regional language regularly or as their primary day-to-day language, especially at home with family or when communicating with Italians from the same town or region. However, to some Italians, speaking a regional language, especially in a formal setting or outside of one's region, may carry a stigma or negative connotations associated with being lower class, uneducated, boorish, or overly informal.

What is never associated with being uneducated?
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A: unanswerable


Problem: Empiricism:

This idea was later developed in ancient philosophy by the Stoic school. Stoic epistemology generally emphasized that the mind starts blank, but acquires knowledge as the outside world is impressed upon it. The doxographer Aetius summarizes this view as "When a man is born, the Stoics say, he has the commanding part of his soul like a sheet of paper ready for writing upon." Later stoics, such as Sextus of Chaeronea, would continue this idea of empiricism in later Stoic writings as well. As Sextus contends "For every thought comes from sense-perception or not without sense-perception and either from direct experience or not without direct experience" (Against the Professors, 8.56-8).

What innate thoughts is a man born with?
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A: unanswerable


Problem: BeiDou Navigation Satellite System:

The second generation of the system, officially called the BeiDou Navigation Satellite System (BDS) and also known as COMPASS or BeiDou-2, will be a global satellite navigation system consisting of 35 satellites, and is under construction as of January 2015[update]. It became operational in China in December 2011, with 10 satellites in use, and began offering services to customers in the Asia-Pacific region in December 2012. It is planned to begin serving global customers upon its completion in 2020.

Which system is also known as COMPANION or BeiDou-23?
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A:
unanswerable