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.

Ex Input:
Passage: The main campus in Provo, Utah, United States sits on approximately 560 acres (2.3 km2) nestled at the base of the Wasatch Mountains and includes 295 buildings. The buildings feature a wide variety of architectural styles, each building being built in the style of its time. The grass, trees, and flower beds on BYU's campus are impeccably maintained. Furthermore, views of the Wasatch Mountains, (including Mount Timpanogos) can be seen from the campus. BYU's Harold B. Lee Library (also known as "HBLL"), which The Princeton Review ranked as the No. 1 "Great College Library" in 2004, has approximately 8 million items in its collections, contains 98 miles (158 km) of shelving, and can seat 4,600 people. The Spencer W. Kimball Tower, shortened to SWKT and pronounced Swicket by many students, is home to several of the university's departments and programs and is the tallest building in Provo, Utah. Furthermore, BYU's Marriott Center, used as a basketball arena, can seat over 22,000 and is one of the largest on-campus arenas in the nation. Interestingly absent on the campus of this church owned university is a campus chapel. Notwithstanding, each Sunday LDS Church services for students are conducted on campus, but due to the large number of students attending these services, nearly all of the buildings and possible meeting spaces on campus are utilized (in addition, many students attend services off campus in LDS chapels in the surrounding communities). Question: How many miles of shelving are in BYU's Harold B. Lee Library?

Ex Output:
98

Ex Input:
Passage: Photorespiration can occur when the oxygen concentration is too high. Rubisco cannot distinguish between oxygen and carbon dioxide very well, so it can accidentally add O2 instead of CO2 to RuBP. This process reduces the efficiency of photosynthesisit consumes ATP and oxygen, releases CO2, and produces no sugar. It can waste up to half the carbon fixed by the Calvin cycle. Several mechanisms have evolved in different lineages that raise the carbon dioxide concentration relative to oxygen within the chloroplast, increasing the efficiency of photosynthesis. These mechanisms are called carbon dioxide concentrating mechanisms, or CCMs. These include Crassulacean acid metabolism, C4 carbon fixation, and pyrenoids. Chloroplasts in C4 plants are notable as they exhibit a distinct chloroplast dimorphism. Question: When does photorespiration happen?

Ex Output:
when the oxygen concentration is too high

Ex Input:
Passage: Three Germanic dialects were originally spoken in the Low Countries: Frisian in the north and along the western coast; Saxon in the east (contiguous with the Low German area); and Franconian in the centre and south. It is the Franconian dialects that is designated as Old Dutch, and that would develop in Middle Dutch and later Modern Dutch. The division in these development phases is mostly conventional, since the transition between them was very gradual. One of the few moments linguists can detect somewhat of a revolution is when the Dutch standard language emerged and quickly established itself. The development of the Dutch language is illustrated by the following sentence in Old, Middle and Modern Dutch: Question: How many different versions of a Germanic language were spoken in the Low Countries?

Ex Output:
Three