An unknot (also known as the trivial knot) can be drawn with any number of crossings. Any possible manipulation of a knot ...
Stars Insider on MSN
Chemical elements that are named after places
The periodic table, which arranges all the elements (radioactive or otherwise) according to their structure, contains 118 ...
Fermented foods make up a third of what we eat and were mostly discovered by accident centuries ago. Now a fermentation ...
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