Shutterstock/Jiranart Aonnoum
Why do loose screws only get looser and not the other way round, even if there seems to be no resistance to the latter?
Bob Falconer,
Winchester, Hampshire, UK
Ivan Chiosea/Alamy
Is it theoretically possible for our memory to become full to the point where it can no longer record information?
Ben Walsh,
London, UK
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