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.

[Q]: In 1872, Russian Alexander Lodygin invented an incandescent light bulb and obtained a Russian patent in 1874. He used as a burner two carbon rods of diminished section in a glass receiver, hermetically sealed, and filled with nitrogen, electrically arranged so that the current could be passed to the second carbon when the first had been consumed. Later he lived in the USA, changed his name to Alexander de Lodyguine and applied and obtained patents for incandescent lamps having chromium, iridium, rhodium, ruthenium, osmium, molybdenum and tungsten filaments, and a bulb using a molybdenum filament was demonstrated at the world fair of 1900 in Paris.
[A]: Who patented an incandescent light bulb in Russia in 1874?


[Q]: 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.
[A]: Which long didactic hexameter poem did Virgil work on for several years?


[Q]: Two major types of atomic bombs were developed by the United States during World War II: a uranium-based device (codenamed "Little Boy") whose fissile material was highly enriched uranium, and a plutonium-based device (see Trinity test and "Fat Man") whose plutonium was derived from uranium-238. The uranium-based Little Boy device became the first nuclear weapon used in war when it was detonated over the Japanese city of Hiroshima on 6 August 1945. Exploding with a yield equivalent to 12,500 tonnes of TNT, the blast and thermal wave of the bomb destroyed nearly 50,000 buildings and killed approximately 75,000 people (see Atomic bombings of Hiroshima and Nagasaki). Initially it was believed that uranium was relatively rare, and that nuclear proliferation could be avoided by simply buying up all known uranium stocks, but within a decade large deposits of it were discovered in many places around the world.
[A]:
What was the uranium-based bomb made by the US in World War II called?