instruction:
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.
question:
Passage: Barbara Harff and Ted Gurr defined genocide as "the promotion and execution of policies by a state or its agents which result in the deaths of a substantial portion of a group ...[when] the victimized groups are defined primarily in terms of their communal characteristics, i.e., ethnicity, religion or nationality." Harff and Gurr also differentiate between genocides and politicides by the characteristics by which members of a group are identified by the state. In genocides, the victimized groups are defined primarily in terms of their communal characteristics, i.e., ethnicity, religion or nationality. In politicides the victim groups are defined primarily in terms of their hierarchical position or political opposition to the regime and dominant groups. Daniel D. Polsby and Don B. Kates, Jr. state that "... we follow Harff's distinction between genocides and 'pogroms,' which she describes as 'short-lived outbursts by mobs, which, although often condoned by authorities, rarely persist.' If the violence persists for long enough, however, Harff argues, the distinction between condonation and complicity collapses."
answer:
Haff and Gurr's definition of opposition included the promotion and execution of what by a state or its agents?


question:
Passage: Even though some proofs of complexity-theoretic theorems regularly assume some concrete choice of input encoding, one tries to keep the discussion abstract enough to be independent of the choice of encoding. This can be achieved by ensuring that different representations can be transformed into each other efficiently.
answer:
What can not be achieved by ensuring different representations can transformed into each other efficiently?


question:
Passage: On April 23, 2008, Dell announced the closure of one of its biggest Canadian call-centers in Kanata, Ontario, terminating approximately 1100 employees, with 500 of those redundancies effective on the spot, and with the official closure of the center scheduled for the summer. The call-center had opened in 2006 after the city of Ottawa won a bid to host it. Less than a year later, Dell planned to double its workforce to nearly 3,000 workers add a new building. These plans were reversed, due to a high Canadian dollar that made the Ottawa staff relatively expensive, and also as part of Dell's turnaround, which involved moving these call-center jobs offshore to cut costs. The company had also announced the shutdown of its Edmonton, Alberta office, losing 900 jobs. In total, Dell announced the ending of about 8,800 jobs in 2007–2008 — 10% of its workforce.
answer:

What year did Dell open its largest Canadian call center?