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This week’s new questions

What is the optimal way to ice a cocktail: fewer big cubes or lots of small ones? And what is the smallest creature that needs to sleep, and what does this tell us about the nature of and need for sleep itself?
What is the best strategy to keep your cocktail cool: fewer big cubes or lots of little ones?
Alexander Spatari/Getty Images

What is the optimal way to ice a cocktail: fewer big cubes or lots of small ones?

Mark Harper
Brighton, UK

2PJC26B Baby mice sleeping in nest in funny position (Mus musculus)
Adrian Eugen/Alamy

What is the smallest creature that needs to sleep and what does this tell us about the nature and need for sleep itself?

Jim McHardy
Clydebank, West Dunbartonshire, UK

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Topics: Last Word