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.

Input: Consider Input: Passage: In the following year, Bell became professor of Vocal Physiology and Elocution at the Boston University School of Oratory. During this period, he alternated between Boston and Brantford, spending summers in his Canadian home. At Boston University, Bell was "swept up" by the excitement engendered by the many scientists and inventors residing in the city. He continued his research in sound and endeavored to find a way to transmit musical notes and articulate speech, but although absorbed by his experiments, he found it difficult to devote enough time to experimentation. While days and evenings were occupied by his teaching and private classes, Bell began to stay awake late into the night, running experiment after experiment in rented facilities at his boarding house. Keeping "night owl" hours, he worried that his work would be discovered and took great pains to lock up his notebooks and laboratory equipment. Bell had a specially made table where he could place his notes and equipment inside a locking cover. Worse still, his health deteriorated as he suffered severe headaches. Returning to Boston in fall 1873, Bell made a fateful decision to concentrate on his experiments in sound. Question: In what year did Bell start to focus on research into sound?

Output: 1873


Input: Consider Input: Passage: In recent years, the city has experienced steady population growth, and has been faced with the issue of accommodating more residents. In 2006, after growing by 4,000 citizens per year for the previous 16 years, regional planners expected the population of Seattle to grow by 200,000 people by 2040. However, former mayor Greg Nickels supported plans that would increase the population by 60%, or 350,000 people, by 2040 and worked on ways to accommodate this growth while keeping Seattle's single-family housing zoning laws. The Seattle City Council later voted to relax height limits on buildings in the greater part of Downtown, partly with the aim to increase residential density in the city centre. As a sign of increasing inner-city growth, the downtown population crested to over 60,000 in 2009, up 77% since 1990. Question: How much increase in population has the inner Seattle city had since 1990?

Output: 77%


Input: Consider Input: Passage: Brain tissue consumes a large amount of energy in proportion to its volume, so large brains place severe metabolic demands on animals. The need to limit body weight in order, for example, to fly, has apparently led to selection for a reduction of brain size in some species, such as bats. Most of the brain's energy consumption goes into sustaining the electric charge (membrane potential) of neurons. Most vertebrate species devote between 2% and 8% of basal metabolism to the brain. In primates, however, the percentage is much higher—in humans it rises to 20–25%. The energy consumption of the brain does not vary greatly over time, but active regions of the cerebral cortex consume somewhat more energy than inactive regions; this forms the basis for the functional brain imaging methods PET, fMRI, and NIRS. The brain typically gets most of its energy from oxygen-dependent metabolism of glucose (i.e., blood sugar), but ketones provide a major alternative source, together with contributions from medium chain fatty acids (caprylic and heptanoic acids), lactate, acetate, and possibly amino acids. Question: Most vertebrates usually devote how much metabolism to the brain?


Output: 2% and 8%