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| How much is a First Class stamp? http://yuvututube.fun/ yuvutu videos Every atom of a given element has its own characteristic resonant frequency. The speed of that vibration is very consistent and very fast 창��혬 there are quadrillions of "ticks" every second. Atomic-clock makers use the regularity of these vibrations to keep time with extreme accuracy. |
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Vincenzo |
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2019-06-11 15:24:20 |
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