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: The City of Charleston Fire Department consists over 300 full-time firefighters. These firefighters operate out of 19 companies located throughout the city: 16 engine companies, two tower companies, and one ladder company. Training, Fire Marshall, Operations, and Administration are the divisions of the department. The department operates on a 24/48 schedule and had a Class 1 ISO rating until late 2008, when ISO officially lowered it to Class 3. Russell (Rusty) Thomas served as Fire Chief until June 2008, and was succeeded by Chief Thomas Carr in November 2008.

Answer: How many companies aren't there in the City of Charleston Fire Department?


Question: Passage: On August 23, 1991,[a] Nintendo released the Super Nintendo Entertainment System, a redesigned version of the Super Famicom, in North America for US$199. The SNES was released in the United Kingdom and Ireland in April 1992 for GB£150, with a German release following a few weeks later. Most of the PAL region versions of the console use the Japanese Super Famicom design, except for labeling and the length of the joypad leads. The Playtronic Super NES in Brazil, although PAL, uses the North American design. Both the NES and SNES were released in Brazil in 1993 by Playtronic, a joint venture between the toy company Estrela and consumer electronics company Gradiente.

Answer: What was a redesign of the Super NES?


Question: Passage: Although coal, hydrocarbons, iron ore, platinum, copper, chromium, nickel, gold and other minerals have been found, they have not been in large enough quantities to exploit. The 1991 Protocol on Environmental Protection to the Antarctic Treaty also restricts a struggle for resources. In 1998, a compromise agreement was reached to place an indefinite ban on mining, to be reviewed in 2048, further limiting economic development and exploitation. The primary economic activity is the capture and offshore trading of fish. Antarctic fisheries in 2000–01 reported landing 112,934 tonnes.

Answer:
What minerals have been found in quantities large enough to exploit?