In what year did Alessandro Volta announce the voltaic pile, the first electric battery? Answer with the four-digit year only.
Bolivia is landlocked. Answer true or false.
In what year was Concorde retired from commercial service? Answer with the four-digit year only.
In what year did the Airbus A320 enter commercial service? Answer with the four-digit year only.
In what year did SpaceX fly astronauts for the first time, on the Demo-2 mission? Answer with the four-digit year only.
In what year did Pan American World Airways cease operations? Answer with the four-digit year only.
In what year did Alain Aspect, John Clauser and Anton Zeilinger win the Nobel Prize in Physics? Answer with the four-digit year only.
Victoria Falls lies on which river? Answer with the river name only, without the word River.
What is the two-character IATA code of Swiss International Air Lines? Answer with the two-character code only.
In what year did the Tunguska event flatten forest in Siberia? Answer with the four-digit year only.
Which mountain range forms most of the border between France and Spain? Answer with the English name only, one word.
In what year was Niels Bohr awarded the Nobel Prize in Physics? Answer with the four-digit year only.
What is the deepest lake in the world? Answer with the lake name only, without the word Lake.
What is the largest freshwater lake in the world by surface area? Answer with the lake name only, without the word Lake.
Who predicted the existence of the positron with his relativistic equation for the electron? Answer with the surname only.
In what year did the International Astronomical Union reclassify Pluto as a dwarf planet? Answer with the four-digit year only.
What is the capital of Nigeria? Answer with the city name only.
In what year did US Airways Flight 1549 land on the Hudson River? Answer with the four-digit year only.
In what year was the Nobel Prize in Physics awarded for the invention of efficient blue LEDs? Answer with the four-digit year only.
Which sea lies between Italy and the Balkan Peninsula? Answer with the sea name only, without the word Sea.
How many meters is one astronomical unit, as defined exactly by the IAU in 2012? Answer with the whole number only.
