I suggest you take a look at this list of physical constants, paying special attention to the "uncertainty" column, and then get back to us on why you don't acc

I suggest you take a look at this list of physical constants, paying special attention to the "uncertainty" column, and then get back to us on why you don't accept any of them except the speed of light. https://en.wikipedia.org/wiki/List_of_physical_constants https://en.wikipedia.org/wiki/List_of_physical_constants