How is the proportion of hydrogen to helium in the Sun's core changing over time?

The percentage of the helium will increase with the decrease in the percentage of the hydrogen.

Explanation:

The conversion of the hydrogen into helium occurs by the nuclear fusion of the hydrogen atoms. This process reduces the hydrogen density and reduces the energy production inside the core region. Typically, in the core region of the hydrogen is converted into the helium by nuclear fusion. Four hydrogen atoms are collectively fuse to form one atom of helium. This process involves the production of heat energy.

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