after hydrogen and oxygen , Which element makes up alomst all if rhe most common substances in your body?

Calcium is what makes most of our body.

Explanation: 99% of the atoms in the human body come from six elements: Hydrogen (62.9%), oxygen (almost 24%), carbon (nearly 12%), nitrogen (nearly 0.6%), calcium (0.24%) and phosphorus (0.14%). Calcium is on the list as it is essential for our skeleton, which contains 99% of the calcium in our body.

igneous rocks are formed by solidification of cooled magma (molten rock), with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks.  

the composition depends on the source magma. there are almost a thousand types of composition found till now.  

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