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: One way to divide hunter-gatherer groups is by their return systems. James Woodburn uses the categories "immediate return" hunter-gatherers for egalitarian and "delayed return" for nonegalitarian. Immediate return foragers consume their food within a day or two after they procure it. Delayed return foragers store the surplus food (Kelly, 31).
answer:
What is the only way to divide hunter-gatherer groups?

question:
Passage: Regular flights to most villages and towns within the state that are commercially viable are challenging to provide, so they are heavily subsidized by the federal government through the Essential Air Service program. Alaska Airlines is the only major airline offering in-state travel with jet service (sometimes in combination cargo and passenger Boeing 737-400s) from Anchorage and Fairbanks to regional hubs like Bethel, Nome, Kotzebue, Dillingham, Kodiak, and other larger communities as well as to major Southeast and Alaska Peninsula communities.
answer:
Which service denies government to subsidise regular air travel in Alaska?

question:
Passage: A key aspect of the Gates Foundation's U.S. efforts involves an overhaul of the country's education policies at both the K-12 and college levels, including support for teacher evaluations and charter schools and opposition to seniority-based layoffs and other aspects of the education system that are typically backed by teachers' unions. It spent $373 million on education in 2009. It has also donated to the two largest national teachers' unions. The foundation was the biggest early backer of the Common Core State Standards Initiative.
answer:
How much did teachers' unions spend on education in 2009?