The calculation is very simple. Just three figures timed to provide an answer.
Not surprisingly, the result of these numbers is measurable. Very. It’s also the basis (among other things) of the metric system which (as I’ve said on this thread previously) is used every day by thousands and thousands of engineers whilst designing buildings, structures, boats, aeroplanes and spaceships. This is because the fundamental principles used in science and engineering have been calculated and checked millions of times and that the car you drive or the house you live in operates as designed.
Now I know you don’t like to commit to anything other than vague conjecture, but I ask again, please provide something that can be checked for validity to support your claims about air and water density as the force which pushed objects down.