In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

[EX Q]: Which category contains a 2 year old tree?, Context: To accurately map the Amazon's biomass and subsequent carbon related emissions, the classification of tree growth stages within different parts of the forest is crucial. In 2006 Tatiana Kuplich organized the trees of the Amazon into four categories: (1) mature forest, (2) regenerating forest [less than three years], (3) regenerating forest [between three and five years of regrowth], and (4) regenerating forest [eleven to eighteen years of continued development]. The researcher used a combination of Synthetic aperture radar (SAR) and Thematic Mapper (TM) to accurately place the different portions of the Amazon into one of the four classifications.
[EX A]: 2

[EX Q]: Why were 78s more popular than 45s in 1954-55?, Context: Some of Elvis Presley's early singles on Sun Records might have sold more copies on 78 than on 45. This is because the majority of those sales in 1954–55 were to the "hillbilly" market in the South and Southwestern United States, where replacing the family 78 rpm player with a new 45 rpm player was a luxury few could afford at the time. By the end of 1957, RCA Victor announced that 78s accounted for less than 10% of Presley's singles sales, essentially announcing the death throes of the 78 rpm format. The last Presley single released on 78 in the United States was RCA Victor 20-7410, I Got Stung/One Night (1958), while the last 78 in the UK was RCA 1194, A Mess Of Blues/Girl Of My Best Friend (1960).
[EX A]: replacing the family 78 rpm player with a new 45 rpm player was a luxury few could afford

[EX Q]: What was Russia a part of?, Context: The post-Imperial nature of Russian subdivision of government changed towards a generally autonomous model which began with the establishment of the USSR (of which Russia was governed as part). It was liberalized in the aftermath of the Soviet Union, with the reforms under Boris Yeltsin preserving much of the Soviet structure while applying increasingly liberal reforms to the governance of the constituent republics and subjects (while also coming into conflict with Chechen secessionist rebels during the Chechen War). Some of the reforms under Yeltsin were scaled back by Vladimir Putin.
[EX A]:
the USSR