Problem: Question: "what machine is mentioned first?" Context: "Eventually, when it was more common for electric recordings to be played back electrically in the 1930s and 1940s, the overall tone was much like listening to a radio of the era. Magnetic pickups became more common and were better designed as time went on, making it possible to improve the damping of spurious resonances. Crystal pickups were also introduced as lower cost alternatives. The dynamic or moving coil microphone was introduced around 1930 and the velocity or ribbon microphone in 1932. Both of these high quality microphones became widespread in motion picture, radio, recording, and public address applications." Answer:

A: radio

Problem: Question: "What kind of government ruled Swaziland?" Context: "Following the elections of 1973, the constitution of Swaziland was suspended by King Sobhuza II who thereafter ruled the country by decree until his death in 1982. At this point Sobhuza II had ruled Swaziland for 61 years, making him the longest ruling monarch in history. A regency followed his death, with Queen Regent Dzeliwe Shongwe being head of state until 1984 when she was removed by Liqoqo and replaced by Queen Mother Ntfombi Tfwala. Mswati III, the son of Ntfombi, was crowned king on 25 April 1986 as King and Ingwenyama of Swaziland." Answer:

A: monarch

Problem: Question: "How is the line significant?" Context: "The city's first bus rapid transit line, the Metrobus, began operation in June 2005, along Avenida Insurgentes. Line 2 opened in December 2008, serving Eje 4 Sur, line 3 opened in February 2011, serving Eje 1 Poniente, and line 4 opened in April 2012 connecting the airport with San Lazaro and Buenavista Station at Insurgentes. As the microbuses were removed from its route, it was hoped that the Metrobus could reduce pollution and decrease transit time for passengers. In June 2013, Mexico City's mayor announced two more lines to come: Line 5 serving Eje 3 Oriente and Line 6 serving Eje 5 Norte. As of June 2013, 367 Metrobus buses transported 850,000 passengers daily." Answer:

A: 367 Metrobus buses transported 850,000 passengers daily

Problem: Question: "Why was it convenient that tyrothricin was discovered?" Context: "In 1939, coinciding with the start of World War II, Rene Dubos reported the discovery of the first naturally derived antibiotic, tyrothricin, a compound of 20% gramicidin and 80% tyrocidine, from B. brevis. It was one of the first commercially manufactured antibiotics universally and was very effective in treating wounds and ulcers during World War II. Gramicidin, however, could not be used systemically because of toxicity. Tyrocidine also proved too toxic for systemic usage. Research results obtained during that period were not shared between the Axis and the Allied powers during the war." Answer:

A:
was very effective in treating wounds and ulcers during World War II