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<span>The Mechanical energy in a mechanical system is determined by adding the potential and kinetic energy together. </span>
Explanation:
Balanced chemical reaction equation will be as follows.

In human body, the neutral iron changes into
(aq) cation. There will be an oxidation-half reaction and a reduction-half reaction. Equations for this reaction are as follows.
Oxidation: 2Fe^{2+}(aq) \rightleftharpoons 2Fe^{3+}(aq) + 2e^{-}[/tex] .... (1)
Reduction:
...... (2)
On adding both equation (1) and (2), the overall reaction equation will be as follows.

Therefore, neutral iron is a part of Heme - b group of Hemoglobin and in an aqueous solution it dissolutes as a part of Heme group. Hence, then it becomes an
cation.
The SI unit for temperature is Kelvin.
The two notations that represent isotopes of the same element is the one that represented in option 1
The lower number is the number of protons while the upper number is the atomic weight
hope this helps