I am not a physicist... so you are implying that the differences in the values is insignificant? To me, it should be exact... or a means should be in place to get the exact value at each given location of sampling... if this was indeed possible, which it may not be. Please advise.
I'm confused on why the dry air gas constant varies:
Dry Air Gas Constant of 286.9 from The Engineering Toolbox
Dry Air Gas Constant of 287.22 from https://www.physicsforums.com/ttp://www.peacesoftware.de/einigewerte/luft_e.html
Dry Air Gas Constant of 287.05 from Brisbane Hot Air Ballooning...