In what year did the United States purchase Alaska from Russia? Answer with the four-digit year only.
In what year did Theodore Maiman demonstrate the first working laser? Answer with the four-digit year only.
What is the two-character IATA code of Lufthansa? Answer with the two-character code only.
Whose constant, symbol h, relates a photon's energy to its frequency? Answer with the surname only.
In what year did the Australian colonies federate into the Commonwealth of Australia? Answer with the four-digit year only.
Which dwarf planet is the largest object in the asteroid belt? Answer with the name only.
The Celsius and Fahrenheit scales show the same reading at minus how many degrees? Answer with the number without the minus sign.
What is the highest mountain in North America? Answer with its official name only, one word.
How many time zones span the contiguous United States? Answer with the whole number only.
Which airline alliance does British Airways belong to? Answer with the alliance's full name.
How many planets in the Solar System have ring systems? Answer with the whole number only.
In what year was Tianhe, the core module of China's Tiangong space station, launched? Answer with the four-digit year only.
In what year did the travel group Thomas Cook and its airline collapse? Answer with the four-digit year only.
In what year did Henry Cavendish carry out his experiment to measure the density of the Earth? Answer with the four-digit year only.
In what year was the Hubble Space Telescope launched? Answer with the four-digit year only.
Who led the team that built Chicago Pile-1, the first nuclear reactor? Answer with the surname only.
What is the capital of Morocco? Answer with the city name only.
In what year did Hayabusa2 return its asteroid Ryugu samples to Earth? Answer with the four-digit year only.
What is the two-character IATA code of Qatar Airways? Answer with the two-character code only.
Which particle carries the electromagnetic force? Answer with the particle name only, in lowercase.
How many degrees of longitude does one standard time zone span? Answer with the whole number only.
