[tex]\it cos\hat M=\sqrt{1-sin^2\hat M}=\sqrt{1-0,8^2}=\sqrt{1-0,64}=\sqrt{0,36}=0,6\ \ \ (1)\\ \\ cos\hat M= \dfrac{OM}{AO}=\dfrac{1,5}{AO}\ \Rightarrow\ AO=\dfrac{1,5}{cos\hat M}\ \ \ \ \ \ (2)\\ \\ \\ (1),\ (2)\ \Rightarrow\ AO=\dfrac{^{10)}1,5}{\ 0,6}=\dfrac{\ 15^{(3}}{6}=\dfrac{5}{2}=2,5\ m[/tex]
