Question: From the 9th century, the Pecheneg nomads began an uneasy relationship with Kievan Rus′. For over two centuries they launched sporadic raids into the lands of Rus′, which sometimes escalated into full-scale wars (such as the 920 war on the Pechenegs by Igor of Kiev reported in the Primary Chronicle), but there were also temporary military alliances (e.g. the 943 Byzantine campaign by Igor). In 968, the Pechenegs attacked and besieged the city of Kiev. Some speculation exists that the Pechenegs drove off the Tivertsi and the Ulichs to the regions of the upper Dniester river in Bukovina. The Byzantine Empire was known to support the Pechenegs in their military campaigns against the Eastern Slavic states.[citation needed]
Is there an answer to this question: What did the Pecheneg frequently not do over the span of two centuries?

Answer: unanswerable


Question: 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.
Is there an answer to this question: What percentage of its workforce did Dell terminate in from 2007 to 2008?

Answer: 10%


Question: In 1978, Jim Shooter became Marvel's editor-in-chief. Although a controversial personality, Shooter cured many of the procedural ills at Marvel, including repeatedly missed deadlines. During Shooter's nine-year tenure as editor-in-chief, Chris Claremont and John Byrne's run on the Uncanny X-Men and Frank Miller's run on Daredevil became critical and commercial successes. Shooter brought Marvel into the rapidly evolving direct market, institutionalized creator royalties, starting with the Epic Comics imprint for creator-owned material in 1982; introduced company-wide crossover story arcs with Contest of Champions and Secret Wars; and in 1986 launched the ultimately unsuccessful New Universe line to commemorate the 25th anniversary of the Marvel Comics imprint. Star Comics, a children-oriented line differing from the regular Marvel titles, was briefly successful during this period.
Is there an answer to this question: When did Chris Claremont become editor-in-chief?

Answer: unanswerable


Question: Wood density is determined by multiple growth and physiological factors compounded into “one fairly easily measured wood characteristic” (Elliott 1970).
Is there an answer to this question: Along with growth, what kind of factors determine the density of wood?

Answer:
physiological