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Like all young mammals, human infants depend on milk for nutrition. Milk is rich in lactose, a disaccharide made from two sugar molecules. Lactose cannot be directly absorbed in the small intestine. T...

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The decision to go to the moon was made in May,nineteen sixty-one.President John Kennedy set the goal in a speech to Congress and the American people."I believe that this nation should commit itself t...

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The majority of the civilian soldiers of the Western democracies, by contrast, just wanted to survive and return to normal life as soon as possible. That also meant that American and British generals ...

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(excerpts from Ice Age movie) The biggest event in two million years is about to go to a whole new dimension. voice 1: Nobody move a muscle. voice 2: We've been living above an entire world and we ...

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Mutations arise at random in a population. Suppose a mutation arises that causes adults to produce lactase in a population that doesn't have any dairy cows. Adults don't drink milk, so producing the l...

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Mr Hastings's technique is to mine the written record of those who took part both actively and passively. His witnesses range from the men whose decisions sent millions to their deaths to the ordinary...

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‘Soon you will go on a long trip. This week, do not wear the colour red. It will bring you bad luck...’ I wonder if this will come true? People have invented many wonderful things. They have create...

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Steve: Is this mostly hard work and a little bit of fun or is it mostly fun and a little bit of hard work? Ludwig: I'd say it's actually mostly both. It is hard work, but when you have passion for wh...