instruction:
In this task, you're given a question, along with a context passage. The passage will not have a direct answer to the question, but can include some information and a clue for the answer. Assuming you can only obtain information about one entity in the passage, your job is to determine whether information from the passage can be used to answer the question. Indicate your choice as 'a' for Yes or 'b' for No.
question:
Question: Who was the last leader of the the country that was established after the year-long siege in 831? Passage:At the time of his accession, Theophilos was obliged to wage wars against the Arabs on two fronts. Sicily was once again invaded by the Arabs, who took Palermo after a year-long siege in 831, established the Emirate of Sicily, and gradually continued to expand across the island. The defence after the invasion of Anatolia by the Abbasid Caliph Al-Ma'mun in 830 was led by the Emperor himself, but the Byzantines were defeated and lost several fortresses. In 831 Theophilos retaliated by leading a large army into Cilicia and capturing Tarsus. The Emperor returned to Constantinople in triumph, but in the autumn he was defeated in Cappadocia. Another defeat in the same province in 833 forced Theophilos to sue for peace (Theophilos offered 100,000 gold dinars and the return of 7,000 prisoners), which he obtained the next year, after the death of Al-Ma'mun.

answer:
b

question:
Question: What was the result for the China football team in the 1988 Olympic Games? Passage:Duan Ju was born in Tianjin. At the age of 17, he was called up to China youth football team. Duan Ju played for Tianjin football Team 2 from 1980 to 1983. From 1984 to 1991, Duan Ju played for Tianjin. In 1988, Duan Ju played for China in the 1988 Asian Cup and football match at the 1988 Olympic Games. In 1990, China lost to Thailand in football match at the 1990 Asian Games. The coach of China, Gao Fengwen quit office, then Duan Ju quit the China national team and returned to Tianjin. in 1992, Duan Ju had gone to Japan and played for NKK SC. In 1993, Duan Ju retired in Japan and returned to China. In 1995, Duan Ju played for Tianjin Yuancheng football club, in the same year, Duan Ju retired again.

answer:
a

question:
Question: How many students graduated from the United States Naval Academy the year that Smith stopped serving as an instructor in Texas? Passage:Smith was born April 30, 1945, in Beaufort, North Carolina. He graduated from East Carteret High School in 1963, and went on to receive a Bachelor of Science degree in Naval Science from the United States Naval Academy in 1967. He subsequently attended the U.S. Naval Postgraduate School at Monterey, California, from which he graduated with a Master of Science degree in Aeronautical Engineering in 1968. He completed naval aviation jet training at Naval Air Station Kingsville, Texas, receiving his aviator wings in May 1969. He was then assigned to the Advanced Jet Training Command (VT-21) where he served as an instructor from May 1969 to March 1971. During the 2-year period that followed, he flew A-6 Intruders and completed a tour in 1972 during the Vietnam War while assigned to Attack Squadron 52 (VA-52) aboard the aircraft carrier . During his deployment with VA-52, Smith took part in Operation Linebacker, the first continuous bombing effort conducted against North Vietnam since 1968.

answer:
a