Resposta :
[tex]\boxed{v_{0y} =v_{0} \cdotp \sin \theta =80\cdotp \sin 30\Longrightarrow v_{0y} =40\ m/s} \\ \\ h=v_{0y} t+\frac{at^{2}}{2} =40\cdotp 4+\frac{-10\cdotp 4^{2}}{2} \Longrightarrow \\ \Longrightarrow \boxed{\boxed{h=80\ m}}[/tex]
[tex]\boxed{v_{0y} =v_{0} \cdotp \sin \theta =80\cdotp \sin 30\Longrightarrow v_{0y} =40\ m/s} \\ \\ h=v_{0y} t+\frac{at^{2}}{2} =40\cdotp 4+\frac{-10\cdotp 4^{2}}{2} \Longrightarrow \\ \Longrightarrow \boxed{\boxed{h=80\ m}}[/tex]