TASK DEFINITION: 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.
PROBLEM: Passage: Bermuda's modern black population contains more than one demographic group. Although the number of residents born in Africa is very small, it has tripled between 2000 and 2010 (this group also includes non-blacks). The majority of blacks in Bermuda can be termed "Bermudian blacks", whose ancestry dates back centuries between the 17th century and the end of slavery in 1834, Bermuda's black population was self-sustaining, with its growth resulting largely from natural expansion. This contrasts to the enslaved blacks of the plantation colonies, who were subjected to conditions so harsh as to drop their birth rate below the death rate, and slaveholders in the United States and the West Indies found it necessary to continue importing more enslaved blacks from Africa until the end of slavery (the same had been true for the Native Americans that the Africans had replaced on the New World plantations). The indigenous populations of many West Indian islands, and much of the South-East of what is now the United States that had survived the 16th- and 17th-century epidemics of European-introduced diseases then became the victims of large-scale slave raiding, with much of the region completely depopulated. When the supply of indigenous slaves ran out, the slaveholders looked to Africa). The ancestry of Bermuda's black population is distinguished from that of the British West Indian black population in two ways: firstly, the higher degree of European and Native American admixture; secondly, the source of the African ancestry.

SOLUTION: What modern population contains one demographic group?

PROBLEM: Passage: Like much of the south Atlantic region of the United States, Jacksonville has a humid subtropical climate (Koppen Cfa), with mild weather during winters and hot and humid weather during summers. Seasonal rainfall is concentrated in the warmest months from May through September, while the driest months are from November through April. Due to Jacksonville's low latitude and coastal location, the city sees very little cold weather, and winters are typically mild and sunny. Summers can be hot and wet, and summer thunderstorms with torrential but brief downpours are common.

SOLUTION: Was city has a tropical climate?

PROBLEM: Passage: All of the ceremonial county of Somerset is covered by the Avon and Somerset Constabulary, a police force which also covers Bristol and South Gloucestershire. The Devon and Somerset Fire and Rescue Service was formed in 2007 upon the merger of the Somerset Fire and Rescue Service with its neighbouring Devon service; it covers the area of Somerset County Council as well as the entire ceremonial county of Devon. The unitary districts of North Somerset and Bath & North East Somerset are instead covered by the Avon Fire and Rescue Service, a service which also covers Bristol and South Gloucestershire. The South Western Ambulance Service covers the entire South West of England, including all of Somerset; prior to February 2013 the unitary districts of Somerset came under the Great Western Ambulance Service, which merged into South Western. The Dorset and Somerset Air Ambulance is a charitable organisation based in the county.

SOLUTION:
In what year was the South Western Ambulance Service established?