This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
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Question: At Maecenas' insistence (according to the tradition) Virgil spent the ensuing years (perhaps 37–29 BC) on the long didactic hexameter poem called the Georgics (from Greek, "On Working the Earth") which he dedicated to Maecenas. The ostensible theme of the Georgics is instruction in the methods of running a farm. In handling this theme, Virgil follows in the didactic ("how to") tradition of the Greek poet Hesiod's Works and Days and several works of the later Hellenistic poets. The four books of the Georgics focus respectively on raising crops and trees (1 and 2), livestock and horses (3), and beekeeping and the qualities of bees (4). Well-known passages include the beloved Laus Italiae of Book 2, the prologue description of the temple in Book 3, and the description of the plague at the end of Book 3. Book 4 concludes with a long mythological narrative, in the form of an epyllion which describes vividly the discovery of beekeeping by Aristaeus and the story of Orpheus' journey to the underworld. Ancient scholars, such as Servius, conjectured that the Aristaeus episode replaced, at the emperor's request, a long section in praise of Virgil's friend, the poet Gallus, who was disgraced by Augustus, and who committed suicide in 26 BC.

Answer: Which long didactic hexameter poem did Virgil work on for several years?


Question: Mean speeds vary greatly, but is typically around 1 m (3 ft) per day. There may be no motion in stagnant areas; for example, in parts of Alaska, trees can establish themselves on surface sediment deposits. In other cases, glaciers can move as fast as 20–30 m (70–100 ft) per day, such as in Greenland's Jakobshavn Isbræ (Greenlandic: Sermeq Kujalleq). Velocity increases with increasing slope, increasing thickness, increasing snowfall, increasing longitudinal confinement, increasing basal temperature, increasing meltwater production and reduced bed hardness.

Answer: In what area of Greenland can glaciers move 20-30m per day?


Question: "Whereas their Majesties have been Graciously Pleased to grant Letters patent to John Lofting of London Merchant for a New Invented Engine for Extinguishing Fires which said Engine have found every great encouragement. The said Patentee hath also projected a Very Useful Engine for starting of beer and other liquors which will deliver from 20 to 30 barrels an hour which are completely fixed with Brass Joints and Screws at Reasonable Rates. Any Person that hath occasion for the said Engines may apply themselves to the Patentee at his house near St Thomas Apostle London or to Mr. Nicholas Wall at the Workshoppe near Saddlers Wells at Islington or to Mr. William Tillcar, Turner, his agent at his house in Woodtree next door to the Sun Tavern London."

Answer:
How many barrels did Lofting promise his beer pump would deliver hourly?