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.

Ex Input:
Passage: It is not clearly documented when the title of the Grand Duke was first introduced, but the importance of the Kiev principality was recognized after the death of Sviatoslav I in 972 and the ensuing struggle between Vladimir the Great and Yaropolk I. The region of Kiev dominated the state of Kievan Rus' for the next two centuries. The Grand Prince ("velikiy kniaz'") of Kiev controlled the lands around the city, and his formally subordinate relatives ruled the other cities and paid him tribute. The zenith of the state's power came during the reigns of Vladimir the Great (980–1015) and Prince Yaroslav I the Wise (1019–1054). Both rulers continued the steady expansion of Kievan Rus' that had begun under Oleg.

Ex Output:
When was the title of Grand Duke introduced?


Ex Input:
Passage: Northwestern fielded its first intercollegiate football team in 1882, later becoming a founding member of the Big Ten Conference. In the 1870s and 1880s, Northwestern affiliated itself with already existing schools of law, medicine, and dentistry in Chicago. The Northwestern University School of Law is the oldest law school in Chicago. As the university increased in wealth and distinction, and enrollments grew, these professional schools were integrated with the undergraduate college in Evanston; the result was a modern research university combining professional, graduate, and undergraduate programs, which gave equal weight to teaching and research. The Association of American Universities invited Northwestern to become a member in 1917.

Ex Output:
 What sports team did Northwestern field its first of in 1982?


Ex Input:
Passage: Houston's economy has a broad industrial base in energy, manufacturing, aeronautics, and transportation. It is also leading in health care sectors and building oilfield equipment; only New York City is home to more Fortune 500 headquarters within its city limits. The Port of Houston ranks first in the United States in international waterborne tonnage handled and second in total cargo tonnage handled. Nicknamed the Space City, Houston is a global city, with strengths in business, international trade, entertainment, culture, media, fashion, science, sports, technology, education, medicine and research. The city has a population from various ethnic and religious backgrounds and a large and growing international community. Houston is the most diverse city in Texas and has been described as the most diverse in the United States. It is home to many cultural institutions and exhibits, which attract more than 7 million visitors a year to the Museum District. Houston has an active visual and performing arts scene in the Theater District and offers year-round resident companies in all major performing arts.

Ex Output:

What city doesn't have more Fortune 500 headquarters than Houston?