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: From 1920, Eisenhower served under a succession of talented generals – Fox Conner, John J. Pershing, Douglas MacArthur and George Marshall. He first became executive officer to General Conner in the Panama Canal Zone, where, joined by Mamie, he served until 1924. Under Conner's tutelage, he studied military history and theory (including Carl von Clausewitz's On War), and later cited Conner's enormous influence on his military thinking, saying in 1962 that "Fox Conner was the ablest man I ever knew." Conner's comment on Eisenhower was, "[He] is one of the most capable, efficient and loyal officers I have ever met." On Conner's recommendation, in 1925–26 he attended the Command and General Staff College at Fort Leavenworth, Kansas, where he graduated first in a class of 245 officers. He then served as a battalion commander at Fort Benning, Georgia, until 1927. Question: How many people were in Eisenhower's class at the Command and General Staff College?
[A]: 245


[Q]: Passage: Albert spent the first six months of 1913 on the training ship HMS Cumberland in the West Indies and on the east coast of Canada. He was rated as a midshipman aboard HMS Collingwood on 15 September 1913, and spent three months in the Mediterranean. His fellow officers gave him the nickname "Mr. Johnson". One year after his commission, he began service in the First World War. He was mentioned in despatches for his action as a turret officer aboard Collingwood in the Battle of Jutland (31 May – 1 June 1916), an indecisive engagement with the German navy that was the largest naval action of the war. He did not see further combat, largely because of ill health caused by a duodenal ulcer, for which he had an operation in November 1917. Question: How many months did Albert spend in the Mediterranean in 1913?
[A]: three months


[Q]: Passage: The universal emergence of atomic hydrogen first occurred during the recombination epoch. At standard temperature and pressure, hydrogen is a colorless, odorless, tasteless, non-toxic, nonmetallic, highly combustible diatomic gas with the molecular formula H2. Since hydrogen readily forms covalent compounds with most non-metallic elements, most of the hydrogen on Earth exists in molecular forms such as in the form of water or organic compounds. Hydrogen plays a particularly important role in acid–base reactions as many acid-base reactions involve the exchange of protons between soluble molecules. In ionic compounds, hydrogen can take the form of a negative charge (i.e., anion) when it is known as a hydride, or as a positively charged (i.e., cation) species denoted by the symbol H+. The hydrogen cation is written as though composed of a bare proton, but in reality, hydrogen cations in ionic compounds are always more complex species than that would suggest. As the only neutral atom for which the Schrödinger equation can be solved analytically, study of the energetics and bonding of the hydrogen atom has played a key role in the development of quantum mechanics. Question: What charge does hydrogen display in ionic compounds when it is called a hydride?
[A]:
negative