This task is about creating an unanswerable question based on a given passage. Construct a question that looks relevant to the given context but is unanswerable. Following are a few suggestions about how to create unanswerable questions:
(i) create questions which require satisfying a constraint that is not mentioned in the passage
(ii) create questions which require information beyond what is provided in the passage in order to answer
(iii) replace an existing entity, number, date mentioned in the passage with other entity, number, date and use it in the question
(iv) create a question which is answerable from the passage and then replace one or two words by their antonyms or insert/remove negation words to make it unanswerable.
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Question: Passage: On April 12, 1980, a military coup led by Master Sergeant Samuel Doe of the Krahn ethnic group overthrew and killed President William R. Tolbert, Jr.. Doe and the other plotters later executed a majority of Tolbert's cabinet and other Americo-Liberian government officials and True Whig Party members. The coup leaders formed the People's Redemption Council (PRC) to govern the country. A strategic Cold War ally of the West, Doe received significant financial backing from the United States while critics condemned the PRC for corruption and political repression.

Answer: Who led a military coup that killed the American ambassador?


Question: Passage: Some alloys occur naturally, such as electrum, which is an alloy that is native to Earth, consisting of silver and gold. Meteorites are sometimes made of naturally occurring alloys of iron and nickel, but are not native to the Earth. One of the first alloys made by humans was bronze, which is made by mixing the metals tin and copper. Bronze was an extremely useful alloy to the ancients, because it is much stronger and harder than either of its components. Steel was another common alloy. However, in ancient times, it could only be created as an accidental byproduct from the heating of iron ore in fires (smelting) during the manufacture of iron. Other ancient alloys include pewter, brass and pig iron. In the modern age, steel can be created in many forms. Carbon steel can be made by varying only the carbon content, producing soft alloys like mild steel or hard alloys like spring steel. Alloy steels can be made by adding other elements, such as molybdenum, vanadium or nickel, resulting in alloys such as high-speed steel or tool steel. Small amounts of manganese are usually alloyed with most modern-steels because of its ability to remove unwanted impurities, like phosphorus, sulfur and oxygen, which can have detrimental effects on the alloy. However, most alloys were not created until the 1900s, such as various aluminium, titanium, nickel, and magnesium alloys. Some modern superalloys, such as incoloy, inconel, and hastelloy, may consist of a multitude of different components.

Answer: What is a man-made alloy of silver and gold?


Question: Passage: The city provides sewage disposal and water supply services, with water coming from the Huron River and groundwater sources. There are two water-treatment plants, one main and three outlying reservoirs, four pump stations, and two water towers. These facilities serve the city, which is divided into five water districts. The city's water department also operates four dams along the Huron River, two of which provide hydroelectric power. The city also offers waste management services, with Recycle Ann Arbor handling recycling service. Other utilities are provided by private entities. Electrical power and gas are provided by DTE Energy. AT&T Inc. is the primary wired telephone service provider for the area. Cable TV service is primarily provided by Comcast.

Answer:
What is the name of the city owned cable company?