Problem: Mechanically controlled variable capacitors allow the plate spacing to be adjusted, for example by rotating or sliding a set of movable plates into alignment with a set of stationary plates. Low cost variable capacitors squeeze together alternating layers of aluminum and plastic with a screw. Electrical control of capacitance is achievable with varactors (or varicaps), which are reverse-biased semiconductor diodes whose depletion region width varies with applied voltage. They are used in phase-locked loops, amongst other applications.
How do cheap variable capacitors vary the separation distance against layers of a plastic and aluminum?
---
Answer: unanswerable

Problem: Nanjing has some of the oldest and finest museums in China. Nanjing Museum, formerly known as National Central Museum during ROC period, is the first modern museum and remains as one of the leading museums in China having 400,000 items in its permanent collection,. The museum is notable for enormous collections of Ming and Qing imperial porcelain, which is among the largest in the world. Other museums include the City Museum of Nanjing in the Chaotian Palace, the Oriental Metropolitan Museum, the China Modern History Museum in the Presidential Palace, the Nanjing Massacre Memorial Hall, the Taiping Kingdom History Museum, Jiangning Imperial Silk Manufacturing Museum, Nanjing Yunjin Museum, Nanjing City Wall Cultural Museum, Nanjing Customs Museum in Ganxi House, Nanjing Astronomical History Museum, Nanjing Paleontological Museum, Nanjing Geological Museum, Nanjing Riverstones Museum, and other museums and memorials such Zheng He Memorial, Jinling Four Modern Calligraphers Memorial.
What collections are the Nanjing Museum famous for?
---
Answer: Ming and Qing imperial porcelain

Problem: Of the approximately 850 municipalities of Thuringia, 126 are classed as towns (within a district) or cities (forming their own urban district). Most of the towns are small with a population of less than 10,000; only the ten biggest ones have a population greater than 30,000. The first towns emerged during the 12th century, whereas the latest ones received town status only in the 20th century. Today, all municipalities within districts are equal in law, whether they are towns or villages. Independent cities (i.e. urban districts) have greater powers (the same as any district) than towns within a district.
How many municipalities in Thuringia are classified as hostile?
---
Answer:
unanswerable