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Calculate the number 873

NUMBERMANIA: Calculate the number 873 using numbers [5, 8, 8, 7, 15, 823] and basic arithmetic operations (+, -, *, /). Each of the numbers can be used only once.

Correct answers: 0

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On Each Bicep

My wife won’t let me get a tattoo of a grizzly bear on each bicep...
She is infringing on my right to bear arms!

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Ultrasonic alarm

In 1953, the first U.S. patent for a burglar alarm operated by ultrasonic sound was issued to Samuel Bagno of New York City (No. 2,655,645) on a system for movement detection in a confined space by intruders or fire. It was manufactured as the Alertronic and first sold in Jun 1950. A sound source produced waves of 19,000 hertz, a frequency too high for normal human hearing. An intruder could be detected by the alarm by a difference in frequency of the reflected waves from the moving body (the Doppler effect). The device would then sound an alarm.

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