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Video Source: www.youtube.com/watch?v=fUlRuiSKzgs
Seismographs are used to measure and sometimes predict earthquakes. Learn how they work. • How Seismograph Works • Dont Forget to subscriber us and like our facebook page thanks • facebook - / hassanbilalofficial • website - http://www.geologisthassan.com • ~-~~-~~~-~~-~ • Please watch: Normal Fault • rarr; • Normal Fault • ~-~~-~~~-~~-~
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