Given the task definition and input, reply with output. 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: BBC Television returned on 7 June 1946 at 15:00. Jasmine Bligh, one of the original announcers, made the first announcement, saying, 'Good afternoon everybody. How are you? Do you remember me, Jasmine Bligh?'. The Mickey Mouse cartoon of 1939 was repeated twenty minutes later.[unreliable source?] Alexandra Palace was the home base of the channel until the early 1950s when the majority of production moved into the newly acquired Lime Grove Studios.[original research?]
What returned on 6 June 1947?