What is your risk of dying every year? It depends on your gender, age, race, where you live, and so many other factors, but it is possible to make a rough estimate of your chances of dying at every age. A person’s statistical risk of dying at every age is useful knowledge for governments, the […]
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When we think about important figures in the history of aviation, Orville and Wilbur Wright obviously spring to mind. However, they probably wouldn’t have been able to fly without the work of Otto Lilienthal, a German aviator, who was known as the flying man. Lilienthal wasn’t the first person to build heavier than air flying
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Why are tennis scores so peculiar? Nobody seems to know the answer, although there are several theories. Tennis has a very illogical scoring system. Both players start on zero, which is called love. From there, the points go to 15, then 30, then 40. If a player on 40 scores one more point, they win
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What game has the best odds in a casino? Blackjack has a 49% chance of winning, which is the best odds you will find in a casino. There are a lot of casinos in the world, although they are illegal in some countries, such as China. China gets around the law by allowing them on
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How does the dome of St. Paul’s Cathedral support itself? The dome of St Paul’s Cathedral in London looks like one massive dome, but it is actually two domes with a cone of bricks between them to give it strength and structural support. St Paul’s Cathedral is one of the main landmarks in London. It
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How do noise cancelling headphones work? They play the sound from around you, but reversed, which cancels out the noise. Sound is a pressure wave that is created by an energy source that makes the molecules of the medium it is travelling through vibrate. Sound can travel through any medium and it travels through some
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Will we ever end up with just one language? We will lose more languages, but it is very unlikely that we would all end up speaking the same language. There is no way of knowing when language appeared. Humans evolved about 300,000 years ago and they probably started by grunting and gesturing at each other.
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What are druids? Druids were members of a priestly class in ancient Celtic cultures. There is not a lot of evidence for druids because they don’t come from a people with a written culture. Most of the records about them were written down by the Roman invaders Gaul and Britain. The Romans suppressed the local
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How does mortar keep the bricks together? It holds the bricks together in a similar way to how glue holds wood together. It also acts as a waterproof sealant. Mortars are not always made of the same material. They are any material that holds together the bricks or stones used to make buildings. Mortars have
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When was the first air conditioning invented? It was invented on July 17th, 1902. The first electrical air conditioning, the predecessor of what we use today, was invented in 1902, but people have been using forms of air conditioning for thousands of years. The first methods to cool buildings relied on architecture. Ancient buildings have
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