You will be given a definition of a task first, then some input of the task.
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.

Passage: In 1970 the country switched its currency from the Bermudian pound to the Bermudian dollar, which is pegged at par with the US dollar. US notes and coins are used interchangeably with Bermudian notes and coins within the islands for most practical purposes; however, banks levy an exchange rate fee for the purchase of US dollars with Bermudian dollars. Bermudian notes carry the image of Queen Elizabeth II. The Bermuda Monetary Authority is the issuing authority for all banknotes and coins, and regulates financial institutions. The Royal Naval Dockyard Museum holds a permanent exhibition of Bermuda notes and coins.
Output:
What did the country switch in 1907?