Question: Which structure of the final fortress is triangular in shape? Passage 1:On 16 June 2009, The Black Eyed Peas released the Guetta-produced "I Gotta Feeling" as their second single from their fifth studio album, The E.N.D.. It became a worldwide hit topping the charts in seventeen countries. It became the most downloaded song of all-time in the United States with almost 7.5 million downloads and in the United Kingdom selling more than 1 million copies. He was nominated twice for his work with The Black Eyed Peas at the 52nd Grammy Awards; in the category Record of the Year for "I Gotta Feeling" and Album of the Year for their album The E.N.D.. In 2010, Guetta co-wrote and produced Kelly Rowland's "Commander" from her third album Here I Am. It peaked at number one on Billboard's Hot Dance Club Songs chart in the United States, and reached top ten positions in Belgium and the United Kingdom. Guetta has also co-produced "Forever and a Day", which was Kelly's next UK single from that album. Guetta also produced the singles "Acapella" and "Scream" for American singer-songwriter Kelis's fifth studio album, Flesh Tone, released on 14 May 2010. "Acapella" was released as the lead single on 23 February 2010 and topped the dance charts in the United Kingdom and United States. On 28 June 2010 American rapper Flo Rida released the single "Club Can't Handle Me" featuring Guetta. The song is included on the soundtrack album to the American 3D dance film Step Up 3D and Flo Rida's third studio album, Only One Flo (Part 1).
 Passage 2:Raveena Tandon is an Indian actress known for her work in Hindi films. She made her debut opposite Salman Khan in the 1991 Patthar Ke Phool, which earned her a Filmfare Award for New Face of the Year. This was followed by a series of unsuccessful films, including Ek Hi Raasta (1993) and Parampara (1993). In 1994, she appeared in eight Hindi films, most of them were commercial successes. Among these were two of the top-grossing films the romantic musical drama Dilwale and the action drama Mohra. The success of the latter marked a turning point in her career, establishing Tandon as a leading actress in Hindi cinema. The same year, her performance in the drama Laadla, earned her a nomination for the Filmfare Award for Best Supporting Actress. Her other film was the comedy Andaz Apna Apna, which though initially a box office disappointment, attained cult status over the years.
 Passage 3:On 7 October 1593, the superintendent of the Venetian Republic founded a revolutionary new kind of settlement: Palmanova. The city’s founding date commemorated the victory of the Christian forces (supplied primarily by the Italian states and the Spanish kingdom) over the Ottoman Turks in the Battle of Lepanto in 1571, during the War of Cyprus. Also honored on 7 October was Saint Justina, chosen as the city's patron saint. Using all the latest military innovations of the 16th century, this small town was a fortress in the shape of a nine-pointed star, designed by Vincenzo Scamozzi. Between the points of the star, ramparts protruded so that the points could defend each other. A moat surrounded the town, and three large, guarded gates allowed entry. The construction of the first circle, with a total circumference of , took 30 years. Marcantonio Barbaro headed a group of Venetian noblemen in charge of building the town, Marcantonio Martinego was in charge of construction, and Giulio Savorgnan acted as an adviser. A second phase of construction took place between 1658 and 1690, and the outer line of fortifications was completed between 1806 and 1813 under the Napoleonic domination. The final fortress consists of: 9 ravelins, 9 bastions, 9 lunettes, and 18 cavaliers.

Output: 3