This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.

[Q]: Passage: At the centre of this wing is the famous balcony with the Centre Room behind its glass doors. This is a Chinese-style saloon enhanced by Queen Mary, who, working with the designer Sir Charles Allom, created a more "binding" Chinese theme in the late 1920s, although the lacquer doors were brought from Brighton in 1873. Running the length of the piano nobile of the east wing is the great gallery, modestly known as the Principal Corridor, which runs the length of the eastern side of the quadrangle. It has mirrored doors, and mirrored cross walls reflecting porcelain pagodas and other oriental furniture from Brighton. The Chinese Luncheon Room and Yellow Drawing Room are situated at each end of this gallery, with the Centre Room obviously placed in the centre. Question: The Principle Corridor features which type of doors?
[A]: mirrored doors


[Q]: Passage: The economic output of the metropolitan area alone is worth more than one third of national GDP around $6.5billion in terms of nominal GDP NR.s 550 billion approximately per year $2200 per capital income approx three times national average. Kathmandu exports handicrafts, artworks, garments, carpets, pashmina, paper; trade accounts for 21% of its finances.[which?] Manufacturing is also important and accounts for 19% of the revenue that Kathmandu generates. Garments and woolen carpets are the most notable manufactured products. Other economic sectors in Kathmandu include agriculture (9%), education (6%), transport (6%), and hotels and restaurants (5%). Kathmandu is famous for lokta paper and pashmina shawls. Question: What is the GDP of Kathmandu?
[A]: 6.5billion


[Q]: Passage: By May 15, Premier Wen Jiabao ordered the deployment of an additional 90 helicopters, of which 60 were to be provided by the PLAAF, and 30 were to be provided by the civil aviation industry, bringing the total of number of aircraft deployed in relief operations by the air force, army, and civil aviation to over 150, resulting in the largest non-combat airlifting operation in People's Liberation Army history. Question: How many helicopter were to be provided by the civil aviation industry?
[A]:
30