On Feb 11, 6:20*pm, Clark wrote:
terry wrote in news:5f088abd-cbda-4dba-a3dd-
:

[snip happened]

Not to detract from your lecture but up in the northern hemisphere we tend to
use 28.96 as the molecular weight of air. Perhaps some of the lighter
molecules settle out in the south? :-)

I shouldnt have been so precise. its just a number I use frequently in
my work that allows for 0.83 v/v % water.( an average value for my
neck of the woods)

After all is said and done, perhaps someone should ask MX to 'splain why
sonic velocity in the atmosphere depends only on temperature...

good luck with that one!