*Question*
Information:  - A record producer or music producer oversees and manages the sound recording and production of a band or performer's music, which may range from recording one song to recording a lengthy concept album. A producer has many roles during the recording process. The roles of a producer vary. He or she may gather musical ideas for the project, collaborate with the artists to select cover tunes or original songs by the artist/group, work with artists and help them to improve their songs, lyrics or arrangements.   - A songwriter is an individual who writes the lyrics, melodies and chord progressions for songs, typically for a popular music genre such as rock or country music. A songwriter can also be called a composer, although the latter term tends to be used mainly for individuals from the classical music genre. The pressure from the music industry to produce popular hits means that songwriting is often an activity for which the tasks are distributed between a number of people. For example, a songwriter who excels at writing lyrics might be paired with a songwriter with a gift for creating original melodies. Pop songs may be written by group members from the band or by staff writers  songwriters directly employed by music publishers. Some songwriters serve as their own music publishers, while others have outside publishers.  - Aliaume Damala Badara Akon Thiam (born April 16, 1973), better known as Akon (pronounced ), is a Senegalese American singer, rapper, songwriter, businessman, record producer and actor. He rose to prominence in 2004 following the release of "Locked Up", the first single from his debut album "Trouble".  - Nadir Khayat, better known by stage name RedOne, (born 9 April 1972) is a Moroccan-Swedish record producer, singer, songwriter and record executive.  - `` Let 's Get Crazy '' is a song co-written by Bilal Hajji , Kinnda Hamid , Nadir Khayat ( RedOne ) and Aliaune Thiam ( Akon ) and recorded by American singer Cassie . A remix by LMFAO was also released .  - Senegal, officially the Republic of Senegal, is a country in West Africa. Senegal is bordered by Mauritania in the north, Mali to the east, Guinea to the southeast, and Guinea-Bissau to the southwest. Senegal also borders The Gambia, a country occupying a narrow sliver of land along the banks of the Gambia River, which separates Senegal's southern region of Casamance from the rest of the country. Senegal also shares a maritime border with Cape Verde. Senegal's economic and political capital is Dakar. It is the westernmost country in the mainland of the Old World, or Afro-Eurasia, and owes its name to the Senegal River, which borders it to the east and north. The name "Senegal" comes from the Wolof "Sunuu Gaal", which means "Our Boat". Senegal covers a land area of almost and has an estimated population of about 13 million. The climate is Sahelian, but there is a rainy season.  - An actor (or actress for females; see terminology) is a person who portrays a character in a performance. The actor performs "in the flesh" in the traditional medium of the theatre, or in modern mediums such as film, radio, and television. The analogous Greek term is, literally "one who answers". The actor's interpretation of their role pertains to the role played, whether based on a real person or fictional character. Interpretation occurs even when the actor is "playing themselves", as in some forms of experimental performance art, or, more commonly; to act, is to create, a character in performance.    What object entity has the relation of 'instance of' with the subject 'let's get crazy '?   Choices: - activity  - april  - art  - cape  - capital  - character  - chord  - classical music  - concept album  - country  - film  - group  - industry  - lyrics  - may  - music  - music genre  - musical  - name  - number  - people  - performance  - population  - process  - production  - region  - republic  - river  - rose  - season  - single  - song  - stage  - term  - terminology  - work  - writing
**Answer**
single

*Question*
Information:  - Sir Alexander Oppenheim , OBE FRSE PMN ( 4 February 1903 -- 13 December 1997 ) was a British mathematician . In mathematics , his most notable contribution is his Oppenheim conjecture .  - Ergodic theory (Ancient Greek: "ergon" work, "hodos" way) is a branch of mathematics that studies dynamical systems with an invariant measure and related problems. Its initial development was motivated by problems of statistical physics.  - Mathematics (from Greek  "máthma", knowledge, study, learning) is the study of topics such as quantity (numbers), structure, space, and change. There is a range of views among mathematicians and philosophers as to the exact scope and definition of mathematics.  - In number theory, the field of Diophantine approximation deals with the approximation of real numbers by rational numbers. It is named after Diophantus of Alexandria.  - A mathematical problem is a problem that is amenable to being represented, analyzed, and possibly solved, with the methods of mathematics. This can be a real-world problem, such as computing the orbits of the planets in the solar system, or a problem of a more abstract nature, such as Hilbert's problems.<br> It can also be a problem referring to the nature of mathematics itself, such as Russell's Paradox.  - A mathematician is someone who uses an extensive knowledge of mathematics in his/her work, typically to solve mathematical problems.  - In Diophantine approximation, the Oppenheim conjecture concerns representations of numbers by real quadratic forms in several variables. It was formulated in 1929 by Alexander Oppenheim and later the conjectured property was further strengthened by Davenport and Oppenheim. Initial research on this problem took the number "n" of variables to be large, and applied a version of the Hardy-Littlewood circle method. The definitive work of Margulis, settling the conjecture in the affirmative, used methods arising from ergodic theory and the study of discrete subgroups of semisimple Lie groups.  - In mathematics, a quadratic form is a homogeneous polynomial of degree two in a number of variables. For example, is a quadratic form in the variables "x" and "y".    What object entity has the relation of 'field of work' with the subject 'alexander oppenheim'?   Choices: - ergodic theory  - mathematician  - mathematics  - nature  - number theory  - physics  - research
**Answer**
number theory