Teacher:In this task, you're given a question, along with three passages, 1, 2, and 3. Your job is to determine which passage can be used to answer the question by searching for further information using terms from the passage. Indicate your choice as 1, 2, or 3.
Teacher: Now, understand the problem? Solve this instance: Question: Which country designed the fighter planes that the Yugoslav Air Force used but were badly maintained? Passage 1:An important portion of the 1999 war between Yugoslavia and the NATO coalition involved combat between the Yugoslav Air Force, which was the predecessor of today's Serbian Air Force, and the opposing air forces of NATO. United States Air Force F-15s and F-16s flying mainly from Italian air force bases attacked the defending Yugoslav fighters—usually MiG-29s, which were in bad shape, due to lack of spare parts and maintenance. A total of six Yugoslav MiG-29s were shot down in 1999, of which three were shot down by USAF F-15s, one by a USAF F-16, and one by a RNAF F-16. One aircraft, according to a Serbian documentary, was hit by friendly fire from the ground. Another four were destroyed on the ground. During the course of the air war, Yugoslav anti-aircraft defenses downed a USAF F-16C and an F-117 Nighthawk, the first stealth aircraft to ever be shot down in combat.
 Passage 2:SR 126 begins in Kingsport at an intersection with SR 93 at its interchange with I-26/US 23 (Exit 4). It goes northeast as a 4-lane undivided highway (known as Wilcox Drive) and immediately has an intersection with its business route, SR 126 Bus (old Wilcox Drive), before going through neighborhoods and industrialized areas before having an interchange with Jared Drive and crossing a bridge over the South Fork Holston River and having an intersection with SR 355. SR 126 continues northeast through more neighborhoods before coming to an intersection with and becoming concurrent with SR 36 (E Center Street), where SR 126 turns southeast to become concurrent with that highway. SR 36/SR 126 then continue southeast to a y-intersection, where they turn onto Fort Henry Drive and become a divided highway. They then come to an intersection with Memorial Boulevard, where SR 126 turns east to leave SR 36 to follow that street. SR 126 becomes undivided once again as it passes through some commercial areas before coming to an interchange with SR 93, where it narrows to 2-lanes and leaves Kingsport, through it still officially remains within the city limits. SR 126 then passes through rural areas and crosses over a ridge before coming to an interchange with I-81 (Exit 66), where it officially exits the city limits of Kingsport. The highway then passes through rural areas again, now paralleling I-81, to enter Blountville, where it has an intersection with SR 75. SR 126 then enters downtown and has an intersection with SR 394. The highway then continues east through downtown before leaving Blountville and continuing east. SR 126 then passes through Walnut Hill before entering Bristol, coming to an end at an intersection with US 11W/SR 1 just south of downtown.
 Passage 3:The Phoenicians settled in Annaba during the 14th century BC. Hippo Regius was a center of early Western Christianity, and it was the site of many Christian synods, one of which was a key site for the dissemination of the books of the New Testament. Augustine of Hippo was bishop here from 396 AD until his death in 430 AD. The city was destroyed in the 5th century by the Vandals. Vandals ruled the city for roughly a century until 534. Gelimer, the King of the Vandals and Alans from 530 to 534 AD, faced with the starvation of his followers and their children, and realizing he had no chance of regaining his kingdom of North Africa, surrendered to Flavius Belisarius, a general of the Byzantine Empire under Justinian I, at Bône. Byzantines then ruled Hippona (Hippo's renamed name after 395) before the Muslim conquest of the Maghreb in 699 AD. Later, Abbasids, Aghlabids, and Fatimids ruled Bona before the rise of the Zirids. It was relocated to its present place after flooding and Banu Hilal the ravages that occurred in 1033 during Hammadid rule. It was attacked by a Pisan and Genovese fleet in 1034 and was conquered by Kingdom of Sicily in 1153. The Almohads took it in 1160.

Student:
1