The copyright holder; unless other arrangements have been made, this is likely to be the creator.
Predominantly, creators.
Copyright law is designed to ascribe exclusive rights to the creator of a work.
Commercial Software
It is gold whose symbol is Au.
Iron
You must mean, "Plutonium", whose symbol is 'Pu'.
The symbol for borilium is B, not to be mistaken with the element Boron, whose symbol is B as well. But there is no known element with the symbol "borilium".
Leader whose reforms included the freeing of citizens who had been forced into slavery
Apollo
there. It's Sodium.
The decibel, whose symbol is dB.
The element with the symbol Au is gold.