Problem: 51st state:

The phrase "51st state" can be used in a positive sense, meaning that a region or territory is so aligned, supportive, and conducive with the United States, that it is like a U.S. state. It can also be used in a pejorative sense, meaning an area or region is perceived to be under excessive American cultural or military influence or control. In various countries around the world, people who believe their local or national culture has become too Americanized sometimes use the term "51st state" in reference to their own countries.

If a country refers to themselves as the "51st state" after cultural changes, what can we assume has changed?
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A: their local or national culture has become too Americanized


Problem: Armenia:

The Armenian Army, Air Force, Air Defence, and Border Guard comprise the four branches of the Armed Forces of the Republic of Armenia. The Armenian military was formed after the collapse of the Soviet Union in 1991 and with the establishment of the Ministry of Defence in 1992. The Commander-in-Chief of the military is the President of Armenia, Serzh Sargsyan. The Ministry of Defence is in charge of political leadership, currently headed by Colonel General Seyran Ohanyan, while military command remains in the hands of the General Staff, headed by the Chief of Staff, who is currently Colonel General Yuri Khatchaturov.

When was the Ministry of Defence founded?
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A: 1992


Problem: Anti-aircraft warfare:

Another potential weapon system for anti-aircraft use is the laser. Although air planners have imagined lasers in combat since the late 1960s, only the most modern laser systems are currently reaching what could be considered "experimental usefulness". In particular the Tactical High Energy Laser can be used in the anti-aircraft and anti-missile role. If current developments continue, some[who?] believe it is reasonable to suggest that lasers will play a major role in air defence starting in the next ten years.

The use of lasers in anti-aircraft warfare is currently considered what?
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A: experimental usefulness


Problem: Houston:

Houston (i/ˈhjuːstən/ HYOO-stən) is the most populous city in Texas and the fourth most populous city in the United States, located in Southeast Texas near the Gulf of Mexico. With a census-estimated 2014 population of 2.239 million people, within a land area of 599.6 square miles (1,553 km2), it also is the largest city in the Southern United States, as well as the seat of Harris County. It is the principal city of Houston–The Woodlands–Sugar Land, which is the fifth most populated metropolitan area in the United States.

What is Houston the non-principle city of?
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A:
unanswerable