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| | What is a Quark? |
 | | Quarks are the only fundamental particles which interact with each other through all four fundamental forces: strong nuclear force, weak nuclear force, electromagnetic force, and gravity. |
 | | There are six known quarks: the up quark, the down quark, the charm quark, the strange quark, the top quark, and the bottom quark. |
 | | The charm quark is about 10 times as massive as that, followed by the bottom quark which is about three times as massive as the last, and finally the top quark which is the most massive of all. |
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