V^2/(Rз+H)=MG/(Rз+H)^2=g*Rз^2/(Rз+H)^2 v^2/(Rз+H)=g*Rз^2/(Rз+H)^2 v^2*(Rз+H)=g*Rз^2 (Rз+H)=g*Rз^2/v^2 H=g*Rз^2/v^2-Rз=10*6400000^2/7500^2-6400000 м = 881777,8 м ~ 882 км