Why does the phrase "Luis no se preocupa POR los demás" use por instead of para? Would it not be para because it is his opinion??

The focus here is not the opinion of the speaker but rather on the reason or motive of the action -- in this case, 'por' means 'about'  in the sense of 'for the sake of' or 'with regard to' ...

Explanation:

the former currency of el salvador who honored an american sailor was:

answer: christopher columbus

the 200 (doscientos colones) was the currency that showed a picture of christopher columbus in front of the bill with a ship - this currency ran from 1892-2001, it was then replaced with the u.s. dollar.

i hope this .