Problem: United States Army:

The army is led by a civilian Secretary of the Army, who has the statutory authority to conduct all the affairs of the army under the authority, direction and control of the Secretary of Defense. The Chief of Staff of the Army, who is the highest-ranked military officer in the army, serves as the principal military adviser and executive agent for the Secretary of the Army, i.e., its service chief; and as a member of the Joint Chiefs of Staff, a body composed of the service chiefs from each of the four military services belonging to the Department of Defense who advise the President of the United States, the Secretary of Defense, and the National Security Council on operational military matters, under the guidance of the Chairman and Vice Chairman of the Joint Chiefs of Staff. In 1986, the GoldwaterNichols Act mandated that operational control of the services follows a chain of command from the President to the Secretary of Defense directly to the unified combatant commanders, who have control of all armed forces units in their geographic or function area of responsibility. Thus, the secretaries of the military departments (and their respective service chiefs underneath them) only have the responsibility to organize, train and equip their service components. The army provides trained forces to the combatant commanders for use as directed by the Secretary of Defense.

Who is the highest-ranked military officer in the army?
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A: The Chief of Staff

Problem: On December 13, 2013, Beyonce unexpectedly released her eponymous fifth studio album on the iTunes Store without any prior announcement or promotion. The album debuted atop the Billboard 200 chart, giving Beyonce her fifth consecutive number-one album in the US. This made her the first woman in the chart's history to have her first five studio albums debut at number one. Beyonce received critical acclaim and commercial success, selling one million digital copies worldwide in six days; The New York Times noted the album's unconventional, unexpected release as significant. Musically an electro-R&B album, it concerns darker themes previously unexplored in her work, such as "bulimia, postnatal depression [and] the fears and insecurities of marriage and motherhood". The single "Drunk in Love", featuring Jay Z, peaked at number two on the Billboard Hot 100 chart. In April 2014, after much speculation in the weeks before, Beyonce and Jay Z officially announced their On the Run Tour. It served as the couple's first co-headlining stadium tour together. On August 24, 2014, she received the Video Vanguard Award at the 2014 MTV Video Music Awards. Knowles also took home three competitive awards: Best Video with a Social Message and Best Cinematography for "Pretty Hurts", as well as best collaboration for "Drunk in Love". In November, Forbes reported that Beyonce was the top-earning woman in music for the second year in a rowearning $115 million in the year, more than double her earnings in 2013. Beyonce was reissued with new material in three forms: as an extended play, a box set, as well as a full platinum edition.
When did Beyonce get her fifth consecutive number one hit album?
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Answer: December 13, 2013

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Unlike previous versions of Windows, Windows 8 was distributed at retail in "Upgrade" licenses only, which require an existing version of Windows to install. The "full version software" SKU, which was more expensive but could be installed on computers without an eligible OS or none at all, was discontinued. In lieu of full version, a specialized "System Builder" SKU was introduced. The "System Builder" SKU replaced the original equipment manufacturer (OEM) SKU, which was only allowed to be used on PCs meant for resale, but added a "Personal Use License" exemption that officially allowed its purchase and personal use by users on homebuilt computers.
What restrictions do Windows upgrade licenses have?
A: require an existing version of Windows to install

Context and question: The 21 nocturnes are more structured, and of greater emotional depth, than those of Field (whom Chopin met in 1833). Many of the Chopin nocturnes have middle sections marked by agitated expression (and often making very difficult demands on the performer) which heightens their dramatic character.
Chopin's nocturnes were more structured than who?
Answer: Field

Question: Old English nouns had grammatical gender, a feature absent in modern English, which uses only natural gender. For example, the words sunne ("sun"), mona ("moon") and wif ("woman/wife") were respectively feminine, masculine and neuter; this is reflected, among other things, in the form of the definite article used with these nouns: seo sunne ("the sun"), se mona ("the moon"), t wif ("the woman/wife"). Pronoun usage could reflect either natural or grammatical gender, when those conflicted (as in the case of wif, a neuter noun referring to a female person).
Is there an answer to this question: What type of gender is present in modern English nouns?

Answer: natural

Problem: Electric motor:

Application of electric motors revolutionized industry. Industrial processes were no longer limited by power transmission using line shafts, belts, compressed air or hydraulic pressure. Instead every machine could be equipped with its own electric motor, providing easy control at the point of use, and improving power transmission efficiency. Electric motors applied in agriculture eliminated human and animal muscle power from such tasks as handling grain or pumping water. Household uses of electric motors reduced heavy labor in the home and made higher standards of convenience, comfort and safety possible. Today, electric motors stand for more than half of the electric energy consumption in the US.

In what domain did electric motors not reduce reliance on humans and animals?
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A:
unanswerable