how do you convert 29.9in hg to 25mm absolute??
I know 1 in =25mm, and I know the difference between psi, psig and psia; but how do you get from 29.9in hg to 25mm absolute? Should it not be about 750mm?
answers are highly appreciated
I also like to thank all the people who answered me before
I do not know how to directly reply to you in this forum

TIA pl