TASK DEFINITION: In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.
PROBLEM: Pieces within this opera include the trio "Zitti, zitti" and the aria "Una voce poco fa." One character in this opera pretends to be the student Lindoro in order to deceive Dr. Bartolo. The title character of this opera repeatedly sings the phrase "della citta" in one aria. That title character aids Count Almaviva in wooing Rosina and sings the aria "Largo al Factotum." For 10 points, name this opera buffa about the servant Figaro, composed by Gioacchino Rossini.

SOLUTION: Fine Arts

PROBLEM: Paulo Ribenboim proved in 1991 that the set of these is Diophantine, and in 1912 Edmund Landau proposed four "unattackable problems" dealing with them, none of which have yet been solved. The theorem named for them states that the number of them less than or equal to n is approximately equal to n divided by the natural logarithm of n. The GIMPS project seeks to find examples of the Mersenne type of this number, ordinary examples of which can be found using the sieve of Eratosthenes. For 10 points, identify these numbers whose only two factors are 1 and itself.

SOLUTION: Social Science

PROBLEM: In one opera by this composer set in Stockholm, the fortune-teller Ulrica prophesizes that Riccardo will be killed by the next man who shakes his hand. This composer of A Masked Ball included "Va, pensiero," or the Chorus of the Hebrew Slaves, in an opera which details the exile of the Jews from Babylon, Nabucco. In addition to the drinking song "Libiamo ne' lieti calici" in an opera about Alfredo and Violetta, this composer wrote an opera which sees the Duke of Mantua sing "La donna e mobile" and another opera about an Egyptian princess. For 10 points, name this Italian composer of Rigoletto, La traviata, and Aida.

SOLUTION:
Fine Arts