Problem: Please answer a question about the following article about Antenna (radio):
Maximum power transfer requires matching the impedance of an antenna system (as seen looking into the transmission line) to the complex conjugate of the impedance of the receiver or transmitter. In the case of a transmitter, however, the desired matching impedance might not correspond to the dynamic output impedance of the transmitter as analyzed as a source impedance but rather the design value (typically 50 ohms) required for efficient and safe operation of the transmitting circuitry. The intended impedance is normally resistive but a transmitter (and some receivers) may have additional adjustments to cancel a certain amount of reactance in order to "tweak" the match. When a transmission line is used in between the antenna and the transmitter (or receiver) one generally would like an antenna system whose impedance is resistive and near the characteristic impedance of that transmission line in order to minimize the standing wave ratio (SWR) and the increase in transmission line losses it entails, in addition to supplying a good match at the transmitter or receiver itself.
What requires matching of the empedance to an antenna system?
A: Maximum power transfer
Problem: Please answer a question about the following article about Premier League:
The league held its first season in 199293 and was originally composed of 22 clubs. The first ever Premier League goal was scored by Brian Deane of Sheffield United in a 21 win against Manchester United. The 22 inaugural members of the new Premier League were Arsenal, Aston Villa, Blackburn Rovers, Chelsea, Coventry City, Crystal Palace, Everton, Ipswich Town, Leeds United, Liverpool, Manchester City, Manchester United, Middlesbrough, Norwich City, Nottingham Forest, Oldham Athletic, Queens Park Rangers, Sheffield United, Sheffield Wednesday, Southampton, Tottenham Hotspur, and Wimbledon. Luton Town, Notts County and West Ham United were the three teams relegated from the old first division at the end of the 199192 season, and did not take part in the inaugural Premier League season.
Originally, how many clubs did the Premier League have?
A: was originally composed of 22 clubs.
Problem: Please answer a question about the following article about Dog:
The health benefits of dogs can result from contact with dogs in general, and not solely from having dogs as pets. For example, when in the presence of a pet dog, people show reductions in cardiovascular, behavioral, and psychological indicators of anxiety. Other health benefits are gained from exposure to immune-stimulating microorganisms, which, according to the hygiene hypothesis, can protect against allergies and autoimmune diseases. The benefits of contact with a dog also include social support, as dogs are able to not only provide companionship and social support themselves, but also to act as facilitators of social interactions between humans. One study indicated that wheelchair users experience more positive social interactions with strangers when they are accompanied by a dog than when they are not. In 2015, a study found that pet owners were significantly more likely to get to know people in their neighborhood than non-pet owners.
What do humans get exposed to with pets that may help them not get sick?
A: immune-stimulating microorganisms
Problem: Please answer a question about the following article about Sichuan:
In the 20th century, as Beijing, Shanghai, Nanjing, and Wuhan had all been occupied by the Japanese during the Second Sino-Japanese War, the capital of the Republic of China had been temporary relocated to Chongqing, then a major city in Sichuan. An enduring legacy of this move is that nearby inland provinces, such as Shaanxi, Gansu, and Guizhou, which previously never had modern Western-style universities, began to be developed in this regard. The difficulty of accessing the region overland from the eastern part of China and the foggy climate hindering the accuracy of Japanese bombing of the Sichuan Basin, made the region the stronghold of Chiang Kai-Shek's Kuomintang government during 1938-45, and led to the Bombing of Chongqing.
To which city was the Chinese capitol relocated to during Japanese occupation in the 20th century?
A:
Chongqing