A new analysis of the ancient Indian Bakhshali manuscript suggests the numerical symbol zero, as we use it today, may be centuries older than previously believed.
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How Do Walkie-Talkies Work?
This technology is going on a hundred years old, but for reliable voice communication across relatively short distances, walkie-talkies are still relevant -- and sometimes preferable to cell phones. Learn how they work in today's episode of BrainStuff, based on this article: http ... Show More
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