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In Spain recently, in temperatures around 34鈦癈, the聽ice cubes in my drink took far longer to melt compared with at home, where it is much colder. Why the difference?

Penny McDonald,

Robin Hood鈥檚 Bay, North Yorkshire, UK

Wheely dirty Why are the front wheels of my car always much聽dirtier than the rear ones?

Rob Jones,

Shetland, UK

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