What cave, found in central Kentucky, is the world's longest cave system?

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What kind of tea takes its name from the Chinese for "Black dragon"?

What must be manufactured by Victorinox or Wenger to be official?

Who created the Rubik's Cube?

Which flower is also known as the "Lent Lily"?

Which country did bagels originate from?

How many spikes are there on the The Statue of Liberty's crown?

What book of short stories has a second section called "Kaa's Hunting"?

What desert is home to the Saguaro Cacti?

How many calves does the average giraffe mother give birth to each time?

What does LPG stands for?

Karl Landsteiner won a Nobel prize in 1930 for which medical discovery?

Who played the leading female part in the 1954 film "A Star Is Born"?

What actor played The Riddler in the original "Batman" TV series?

Who were the two villains in the movie "Batman Returns"?

When was Indira Gandhi assassinated?