Q: The 'Mach' speed measurement (for example Mach 1, or Mach 2, etc) is based essentially on multiples of the speed of what?
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A: sound

Q: Television: in 2011, who returned to present Gardeners World, having previously presented the programme from 2003 to 2008?
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A: monty don

Q: Which country has the internet domain .au?
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A:
australia