V_air * ro * g==S * h * ro * g==p==F/S==Shrog/S==hrog => Vair * ro * g=h * ro * g => V_air==h 😉 Sh=h => S=1 => pir^2+hpi2r=1 => where pir^2=2pir => 2pir+h2pir=1 => Perim+hPerim=1 [...] Read more