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.

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?
when the oxygen concentration is too high

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?
98

Passage: Stepper motors can be rotated to a specific angle in discrete steps with ease, and hence stepper motors are used for read/write head positioning in computer floppy diskette drives. They were used for the same purpose in pre-gigabyte era computer disk drives, where the precision and speed they offered was adequate for the correct positioning of the read/write head of a hard disk drive. As drive density increased, the precision and speed limitations of stepper motors made them obsolete for hard drivesthe precision limitation made them unusable, and the speed limitation made them uncompetitivethus newer hard disk drives use voice coil-based head actuator systems. (The term "voice coil" in this connection is historic; it refers to the structure in a typical (cone type) loudspeaker. This structure was used for a while to position the heads. Modern drives have a pivoted coil mount; the coil swings back and forth, something like a blade of a rotating fan. Nevertheless, like a voice coil, modern actuator coil conductors (the magnet wire) move perpendicular to the magnetic lines of force.) Question: To what device does the term, "voice coil" historically refer?
the structure in a typical (cone type) loudspeaker