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 second time period mentioned?, Context: European colonialism in the Sahara began in the 19th century. France conquered the regency of Algiers from the Ottomans in 1830, and French rule spread south from Algeria and eastwards from Senegal into the upper Niger to include present-day Algeria, Chad, Mali then French Sudan including Timbuktu, Mauritania, Morocco (1912), Niger, and Tunisia (1881). By the beginning of the 20th century, the trans-Saharan trade had clearly declined because goods were moved through more modern and efficient means, such as airplanes, rather than across the desert.

Answer: 1830

Question: Which acronym is the shortest among ANSI, IESNA and ASHRAE?, Context: The Illuminating Engineering Society of North America (IESNA), in conjunction with organizations like ANSI and ASHRAE, publishes guidelines, standards, and handbooks that allow categorization of the illumination needs of different built environments. Manufacturers of lighting equipment publish photometric data for their products, which defines the distribution of light released by a specific luminaire. This data is typically expressed in standardized form defined by the IESNA.

Answer: ANSI

Question: What types of academics were there?, Context: 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 192526 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.

Answer:
including Carl von Clausewitz's On War