In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
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Question: What is the official name for the soldier's specialized area of expertise?, Context: Training in the U.S. Army is generally divided into two categories – individual and collective. Basic training consists of 10 weeks for most recruits followed by Advanced Individualized Training (AIT) where they receive training for their military occupational specialties (MOS). Some individuals MOSs range anywhere from 14–20 weeks of One Station Unit Training (OSUT), which combines Basic Training and AIT. The length of AIT school varies by the MOS The length of time spent in AIT depends on the MOS of the soldier, and some highly technical MOS training may require many months (e.g., foreign language translators). Depending on the needs of the army, Basic Combat Training for combat arms soldiers is conducted at a number of locations, but two of the longest-running are the Armor School and the Infantry School, both at Fort Benning, Georgia.

Answer: military occupational specialties (MOS)


Question: It became easier to move around in non-deep water thanks to what living entity?, Context: The tide-predicting machine invented by Sir William Thomson in 1872 was of great utility to navigation in shallow waters. It used a system of pulleys and wires to automatically calculate predicted tide levels for a set period at a particular location.

Answer: Sir William Thomson


Question: what type of string is mentioned third to last?, Context: Samuel Adelstein described the Lombardi mandolin in 1893 as wider and shorter than the Neapolitan mandolin, with a shallower back and a shorter and wider neck, with six single strings to the regular mandolin's set of 4. The Lombardi was tuned C, D, A, E, B, G. The strings were fastened to the bridge like a guitar's. There were 20 frets, covering three octaves, with an additional 5 notes. When Adelstein wrote, there were no nylon strings, and the gut and single strings "do not vibrate so clearly and sweetly as the double steel string of the Neapolitan."

Answer:
gut