What's the Kennection? #6

Welcome to the all-new edition of Kennections, a weekly quiz created by Jeopardy! champion/co-host Ken Jennings. Here's how to play: All five answers to the questions below have something in common. Can you figure it out?

1. In 1687, Isaac Newton invented classical mechanics by publishing his famous three laws of what?

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2.  What name was shared by pigs on the TV shows Green Acres and Kipper?

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3.  What tough Boston detective is “for hire” in 40 novels by Robert B. Parker?

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4.  In 2013, Argentina’s Jorge Bergoglio became the first person from the Southern Hemisphere named to what office?

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5.  According to Nazi playwright Hanns Johst, “When I hear the word culture, I reach for my” what American pistol?

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