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Only a few elements can be permanent magnets - iron is one. Copper is not. But if you pass an electric current through any metal it becomes a magnet - an electromagnet. But how does this work? Well...
Why are gas stations always built right next to other gas stations? Why is it that I can drive for a mile without finding a coffee shop and then stumble across three on the same corner? Why do grocery...
we've all seen these pictures in magazines, on the internet, everywhere of people going from a certain physique either fat or really skinny to a very muscular physique. Most of the time it’s...
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