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.

Ex Input:
Question: What other teammates had Roberts had before partnering with Lawson? Passage:Lawson accepted an offer from Yamaha to contest the 500cc World Championship as Kenny Roberts' teammate for the 1983 season. Lawson spent the 1983 season learning the ropes of the Grand Prix circuit. In 1984, Lawson began winning regularly and won the 1984 World Championship. It would mark the first of four world titles Lawson would go on to win. In 1985, he won the prestigious Imola 200 pre-season race. After winning two more titles for Yamaha in 1986 and 1988, Lawson shocked the racing world by announcing he would be leaving Yamaha to sign with their arch-rivals Rothmans Honda as teammate to his own archrival, Australia's 1987 World Champion Wayne Gardner. By switching teams, Lawson also fulfilled his desire to work with Erv Kanemoto. After Gardner crashed and broke his leg during the third round at Laguna Seca, Lawson went on to win the 1989 title for Honda, becoming the first rider to win back-to-back championships on machines from different manufacturers. By winning with both Yamaha and Honda, Lawson silenced his critics who believed he would not be as successful away from the factory Marlboro Yamaha team.

Ex Output:
b

Ex Input:
Question: How long had A&M Records been in business at the time the Carpenters signed a contract with them? Passage:The siblings were born in New Haven, Connecticut, and moved to Downey, California, in 1963. Richard took piano lessons as a child, progressing to California State University, Long Beach, while Karen learned the drums. They first performed together as a duo in 1965 and formed the jazz-oriented Richard Carpenter Trio followed by the middle-of-the-road group Spectrum. Signing as Carpenters to A&M Records in 1969, they achieved major success the following year with the hit singles "(They Long to Be) Close to You" and "We've Only Just Begun". Subsequently, the duo's brand of melodic pop produced a record-breaking run of hit recordings on the American Top40 and Adult Contemporary charts, and they became leading sellers in the soft rock, easy listening and adult contemporary music genres. The Carpenters had three number-one singles and five number-two singles on the Billboard Hot100 and fifteen number-one hits on the Adult Contemporary chart, in addition to twelve top-10 singles. They have sold more than 90million records worldwide, making them one of the best-selling music artists of all time. The duo toured continually during the 1970s, which put them under increased strain; Richard took a year off in 1979 after he had become addicted to Quaaludes, while Karen suffered from anorexia nervosa.

Ex Output:
a

Ex Input:
Question: How old was Moore when he was promoted to Lieutenant Colonel? Passage:The Battle of Ia Drang was the first major battle between the United States Army and the People's Army of Vietnam (PAVN), also referred to as the North Vietnamese Army (NVA), and was part of the Pleiku Campaign conducted early in the Vietnam War. It comprised two main engagements, centered on two previously scouted helicopter landing zones (LZs), known as LZ X-Ray and LZ Albany. The first involved the 1st Battalion, 7th Cavalry Regiment and supporting units under the command of Lieutenant Colonel Hal Moore, and took place November 1416, 1965 at LZ X-Ray, located at the eastern foot of the Chu Pong Massif in the central highlands of Vietnam. The second engagement involved the 2nd Battalion, 7th Cavalry Regiment plus supporting units under the command of Lieutenant Colonel Robert McDade, and took place on November 17 at LZ Albany, farther north in the Ia Drang Valley. It is notable for being the first large scale helicopter air assault and also the first use of Boeing B-52 Stratofortress strategic bombers in a tactical support role. Surrounded and under heavy fire from a numerically superior force, the American forces at LZ X-ray were able to hold off and drive back the North Vietnamese forces over three days of battle, largely through the support of both air power and heavy artillery bombardment, which the North Vietnamese lacked. LZ X-ray was considered an American tactical victory, as the Americans were able to exact an almost 10:1 kill ratio. At LZ Albany, the American forces were ambushed in close quarters. They were unable to use air and artillery support due to the close engagement of the North Vietnamese, the American forces were badly defeated, suffering an over-50% casualty rate before being extricated from the battle. Both sides, therefore, were able to claim victory in the battle.

Ex Output:
b