Context: 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.

Question: Who patented an incandescent light bulb in Russia in 1874?
Answer: Alexander Lodygin

Question: What did Lodygin use as a burner in his lamp?
Answer: two carbon rods

Question: In what year did Lodygin demonstrate a lamp at the World's Fair?
Answer: 1900

Question: What did Lodygin change his name to after moving to the USA?
Answer: Alexander de Lodyguine

Question: When did Lodygin invent his first lamp?
Answer: 1872

Question: Who did not patent an incandescent light bulb in 1872?
Answer: Unanswerable

Question: Who did not demonstrate at the world fair in 1900 in Paris?
Answer: Unanswerable

Question: When did Anxander Lodygin change his name?
Answer: Unanswerable

Question: Who invented his first lamp in the 1700's?
Answer: Unanswerable

Question: What did Lodygin not use as a burner in his lamp?
Answer: Unanswerable