Here is a question about this article: The actual antenna which is transmitting the original wave then also may receive a strong signal from its own image from the ground. This will induce an additional current in the antenna element, changing the current at the feedpoint for a given feedpoint voltage. Thus the antenna's impedance, given by the ratio of feedpoint voltage to current, is altered due to the antenna's proximity to the ground. This can be quite a significant effect when the antenna is within a wavelength or two of the ground. But as the antenna height is increased, the reduced power of the reflected wave (due to the inverse square law) allows the antenna to approach its asymptotic feedpoint impedance given by theory. At lower heights, the effect on the antenna's impedance is very sensitive to the exact distance from the ground, as this affects the phase of the reflected wave relative to the currents in the antenna. Changing the antenna's height by a quarter wavelength, then changes the phase of the reflection by 180, with a completely different effect on the antenna's impedance.
What is the answer to this question: What is altered because of the proximity to the ground?
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So... antenna's impedance

The problem: Answer a question about this article:
Of the estimated 8.8 million Jews living in Europe at the beginning of World War II, the majority of whom were Ashkenazi, about 6 million more than two-thirds were systematically murdered in the Holocaust. These included 3 million of 3.3 million Polish Jews (91%); 900,000 of 1.5 million in Ukraine (60%); and 5090% of the Jews of other Slavic nations, Germany, Hungary, and the Baltic states, and over 25% of the Jews in France. Sephardi communities suffered similar depletions in a few countries, including Greece, the Netherlands and the former Yugoslavia. As the large majority of the victims were Ashkenazi Jews, their percentage dropped from nearly 92% of world Jewry in 1931 to nearly 80% of world Jewry today. The Holocaust also effectively put an end to the dynamic development of the Yiddish language in the previous decades, as the vast majority of the Jewish victims of the Holocaust, around 5 million, were Yiddish speakers. Many of the surviving Ashkenazi Jews emigrated to countries such as Israel, Canada, Argentina, Australia, and the United States after the war.
The percentage of Ashkenazi Jews went from being close to 92% of all Jews in the world in 1931 prior to WWII to what percentage today?
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The answer: nearly 80%

Problem: Please answer a question about the following article about Armenia:
Football is also popular in Armenia. The most successful team was the FC Ararat Yerevan team of the 1970s who won the Soviet Cup in 1973 and 1975 and the Soviet Top League in 1973. The latter achievement saw FC Ararat gain entry to the European Cup where despite a home victory in the second leg they lost on aggregate at the quarter final stage to eventual winner FC Bayern Munich. Armenia competed internationally as part of the USSR national football team until the Armenian national football team was formed in 1992 after the split of the Soviet Union. Armenia have never qualified for a major tournament although recent improvements saw the team to achieve 44th position in the FIFA World Rankings in September 2011. The national team is controlled by the Football Federation of Armenia. The Armenian Premier League is the highest level football competition in Armenia, and has been dominated by FC Pyunik in recent seasons. The league currently consists of eight teams and relegates to the Armenian First League.
Which team did the FC Ararat lose to in the European Cup?
A: FC Bayern Munich

Question: Read this and answer the question

Bern lies on the Swiss plateau in the Canton of Bern, slightly west of the centre of Switzerland and 20 km (12 mi) north of the Bernese Alps. The countryside around Bern was formed by glaciers during the most recent Ice Age. The two mountains closest to Bern are Gurten with a height of 864 m (2,835 ft) and Bantiger with a height of 947 m (3,107 ft). The site of the old observatory in Bern is the point of origin of the CH1903 coordinate system at 465708.66N 72622.50E / 46.9524056N 7.4395833E / 46.9524056; 7.4395833.

What helped form the Bern countryside?
Answer: glaciers

Problem: In the city, the population was spread out with 21.9% at age 19 and under, 14.3% from 20 to 24, 33.2% from 25 to 44, 20.4% from 45 to 64, and 10.1% who were 65 years of age or older. The median age was 30.8 years. For every 100 females, there were 92.0 males. For every 100 females age 18 and over, there were 89.9 males. There were 252,699 households, of which 20.4% had children under the age of 18 living in them, 25.5% were married couples living together, 16.3% had a female householder with no husband present, and 54.0% were non-families. 37.1% of all households were made up of individuals and 9.0% had someone living alone who was 65 years of age or older. The average household size was 2.26 and the average family size was 3.08.
What percentage of the City of Bostons population is 19 and under?
The answer is the following: 21.9%

Input: Article: Anthropologists have contributed to the debate by shifting the focus of research: One of the first challenges for the researcher wishing to carry out empirical research in this area is to identify an appropriate analytical tool. The concept of boundaries is useful here for demonstrating how identity works. In the same way as Barth, in his approach to ethnicity, advocated the critical focus for investigation as being "the ethnic boundary that defines the group rather than the cultural stuff that it encloses" (1969:15), social anthropologists such as Cohen and Bray have shifted the focus of analytical study from identity to the boundaries that are used for purposes of identification. If identity is a kind of virtual site in which the dynamic processes and markers used for identification are made apparent, boundaries provide the framework on which this virtual site is built. They concentrated on how the idea of community belonging is differently constructed by individual members and how individuals within the group conceive ethnic boundaries.

Now answer this question: Boundaries are frequently used by researchers to help define what?

Output:
identity