Answer: Explanation:
Calcium (Ca), chemical element, one of the alkaline-earth metals of Group 2 (IIa) of the periodic table. It is the most abundant metallic element in the human body and the fifth most abundant element in Earth's crust.
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Calcium.
atomic number 20
oxidation state +2
electron configuration 1s22s22p63s23p64s2
Explanation:
The answer to your question would be D Volumetric Flask
Hydrogen and oxygen and nitrogen.