Resposta :
[tex]\large\boxed{\begin{array}{l}\underline{\sf Veja\,a\,figura\,que\,eu\,anexei}\\\rm tg(60^\circ)=\dfrac{h}{80}\\\rm h=80tg(60^\circ)\\\rm h=80\cdot\sqrt{3}\\\sf admitindo\,\sqrt{3}=1,73\,temos\\\rm h=80\cdot1,73\\\rm h=138,4\,m\end{array}}[/tex]
