BRAIN TEASERS

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Which is a winning combination of digits?

The computer chose a secret code (sequence of 4 digits from 1 to 6). Your goal is to find that code. Black circles indicate the number of hits on the right spot. White circles indicate the number of hits on the wrong spot.

Correct answers: 0

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Mike Birbiglia: Sex and Pizza

Sex and pizza, they say, are similar. When its good, its good. When its bad, you get it on your shirt.

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Three element vacuum tube

In 1907, the three-element vacuum tube was issued a U.S. patent to its inventor, Dr Lee de Forest as a “device for amplifying feeble electric currents - such, for example, as telephone currents” (No. 841,387). The tube was evacuated, with some remaining conducting gas molecules, and it was suggested using for the heated electrode such material as platinum, tantalum or carbon. He had made a public annoucement of his device a few months earlier, on 20 Oct 1906 at a meeting of the American Institute of Electrical Engineers held in New York City. On 18 Feb 1908, he received another patent for the grid electrode tube (No. 879,532).

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