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Rev. Green

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Rev. Green
An infinite number of points A are placed at random on an infinitely long line. A second infinity of points B are also placed at random on the line. How many B's coincide with one or more A's on...
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Rev. Green
Should we all walk/jog/run in a clockwise direction when there is an alternative return route to avoid those coming the other way? Clockwise is easy to remember: it's the way round a roundabout. Right...
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Rev. Green
The high-power pumps can empty the reservoir in four months and consume large amounts of energy. A hundred pipes could empty it quicker and cost little.
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Rev. Green
What numbers can I put into plastic recycling? I know that 1 and 2 are okay. Are there others? The council says "anything bottle shaped"!...
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Is anyone else irritated by not knowing in The Planets series which scenes are real and which are computer-generated. It would be easy to include an on-screen symbol to tell us which. Wildlife and...
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Gravity obeys the inverse-square law at ordinary distances. To make it obey the same law at large distances we invent dark matter, and to keep it on track at vast distances we invent dark energy....
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Ducks fly in V-formation to save energy. When swimming, should the V be sharper or flatter? Does it depend on viscosity, or speed of sound in the medium, or both?
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Our TV failed after 24 years, so we've coupled the Freeview box to a monitor. The box has five formats, from cinema to square-ish, and the monitor has three formats. Some combinations give tall thin...
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Please tell me the third column to show where I keep going wrong.
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How do Black Holes swallow matter? They have high gravity, but almost every object that approaches them should go into orbit in the same way that almost everything in the Solar System orbits the Sun....
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If I receive income on Tuesday and give some to my son on Thursday, he never has to pay tax on it even if I die within seven years. If I wait twenty years to give it, it then becomes savings, and he...
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What is the spacing of isobars on BBC Weather? Is it always the same? It seems about four millibars.
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Trees are symmetrical. Why haven't some evolved with more leaves in sunlight, the South side in the Northern hemisphere.
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I need the current value of a brooch which was valued at £100 in 2005. Is the indexation value available anywhere?...
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How does a black hole attract matter if nothing, except a small amount of Hawking radiation, can escape?
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I'd like to buy a better mobile telephone, one which can show email and the odd web page. Can they use the wifi router when at home? It would be good to know what is available before approaching a...
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UV 2 is benign, UV 4 begs sun cream, UV 6 requires respect, but is the scale linear (like Volts), logarithmic (like dB or Richter), linear with an offset base (like Celsius or British dress sizes);...
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At 10 000 m altitude a balloon is cold, but a meteor is hot. What would be the temperature of the nose of an aircraft flying at (say) 600 km/h? Ignore conduction and radiation, or masochists can...
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When someone plays a stringed instrument - not a piano - left-handed, do they reverse the order of the strings? i.e. does a left-handed guitarist or violinist still have the higher-pitched strings...
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How could we detect a magnetic monopole, and why is it said that if a single magnetic monopole exists then all the electrons in the Universe must have the same rest mass?

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