http://ed.ted.com/featured/H8AVpKzt#review

https://www.theguardian.com/science/2017/feb/13/can-you-solve-it-the-mystery-of-portias-caskets

Alex Bellos has a puzzle every 2 weeks in The Guardian.  The link just above is his tribute to Raymund Smullyan.  The link above that is different, but very interesting.
How can you calculate the speed of light easily"
http://www.npr.org/sections/thesalt/2017/04/17/523609388/peep-show-watch-us-calculate-the-speed-of-light-with-stale-easter-treats"utm_campaign=storyshare&utm_source=facebook.com&utm_medium=social

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