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When I go walking with my wife, six of her paces are equivalent to five of mine. Does this mean she gets more exercise than me?

Derek Shotton, Havant, Hampshire, UK

If plastic is inert, why does it have a taste and smell? Plastic bin bags have a strong smell when first opened and water left in plastic bottles can acquire a distinct taste.

Louis Chambers, London, UK

Why do some people like gambling so much? What is the evolutionary root of this behaviour?

Sergey Kasatkin, San Francisco, California, US

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