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.

[Q]: Passage: A TiVo service update in July 2008 allowed the system to search and play YouTube videos. In January 2009, YouTube launched "YouTube for TV", a version of the website tailored for set-top boxes and other TV-based media devices with web browsers, initially allowing its videos to be viewed on the PlayStation 3 and Wii video game consoles. In June 2009, YouTube XL was introduced, which has a simplified interface designed for viewing on a standard television screen. YouTube is also available as an app on Xbox Live. On November 15, 2012, Google launched an official app for the Wii, allowing users to watch YouTube videos from the Wii channel. An app is also available for Wii U and Nintendo 3DS, and videos can be viewed on the Wii U Internet Browser using HTML5. Google made YouTube available on the Roku player on December 17, 2013 and in October 2014, the Sony PlayStation 4.
[A]: What did YouTube launch in January 2008?

[Q]: Passage: To be considered 'enriched', the uranium-235 fraction should be between 3% and 5%. This process produces huge quantities of uranium that is depleted of uranium-235 and with a correspondingly increased fraction of uranium-238, called depleted uranium or 'DU'. To be considered 'depleted', the uranium-235 isotope concentration should be no more than 0.3%. The price of uranium has risen since 2001, so enrichment tailings containing more than 0.35% uranium-235 are being considered for re-enrichment, driving the price of depleted uranium hexafluoride above $130 per kilogram in July 2007 from $5 in 2001.
[A]: Between what percent fraction range of uranium-235 is uranium regarded as unenriched?

[Q]: Passage: Washington University has a large number of student-run musical groups on campus, including 12 official a cappella groups. The Pikers, an all-male group, is the oldest such group on campus. The Greenleafs, an all-female group is the oldest (and only) female group on campus. The Mosaic Whispers, founded in 1991, is the oldest co-ed group on campus. They have produced 9 albums and have appeared on a number of compilation albums, including Ben Folds' Ben Folds Presents: University A Cappella! The Amateurs, who also appeared on this album, is another co-ed a cappella group on campus, founded in 1991. They have recorded seven albums and toured extensively. After Dark is a co-ed a cappella group founded in 2001. It has released three albums and has won several Contemporary A Capella Recording (CARA) awards. In 2008 the group performed on MSNBC during coverage of the vice presidential debate with specially written songs about Joe Biden and Sarah Palin. The Ghost Lights, founded in 2010, is the campus's newest and only Broadway, Movies, and Television soundtrack group. They have performed multiple philanthropic concerts in the greater St. Louis area and were honored in November 2010 with the opportunity to perform for Nobel Laureate Douglass North at his birthday celebration.
[A]:
How many member are there in The Pikers a cappella group?