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xkcd #3131: Cesium
(imgs.xkcd.com)
Title text:
Someday I hope to find a way to mess up a recipe so badly that it draws the attention of the International Air Transport Association, the International Mathematical Olympiad, or the NSA.
Transcript:
Transcript will show once it’s been added to explainxkcd.com
Source: https://xkcd.com/3131/
Smuggling and clandestine military operations with zero regard for public safety are more common than you’d think, because when things go wrong nobody gets punished.