In which European city are the headquarters of OPEC?

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Who is pictures on the US Purple Heart medal?

How many camels carried the 117,000 volumes of Abdul Kassem Ismael's library?

What is the device that measures the number of steps you take when walking or running?

What is replaced in the hand of William Shakespeare's graveside memorial bust each year on the anniversary of his death?

Which writers works include "The Dark Eyes of London', "Four Just Men" and "Sanders of the River"?

Which US state shares a border with the Canadian province of New Brunswick?

Who won a Grammy Award for his song "I Left my Heart in San Francisco"?

What is the square root of one-quarter?

Who directed the Michael Jackson music videos for "Thriller" and "Black and White"?

Who played the role of Bud Bundy on the TV show "Married with Children"?

What duo starred in the 1969 movie "Butch Cassidy and the Sundance Kid"?

What TV series starred trail hands Gil Favor and Rowdy Yates?

In what decade did North and South Korea declare themselves sovereign from each other?

What year was the Battle of Bannockburn?

In "Ready Player One" by Ernest Cline, who must the player defeat in order to obtain the copper key?