The horizontal distance (s)= ut+[tex] \frac{1}{2} g t^{2} [/tex]
Time taken by the ball to hit the ground,
h=[tex] \frac{1}{2} g t^{2} [/tex]
h=60
60= [tex] \frac{1}{2}*10* t^{2} [/tex]
60=5[tex] t^{2} [/tex]
[tex] t^{2}= \frac{60}{5} [/tex]
t=[tex] \sqrt{12} [/tex]
Replacing for distance covered
H=ut+[tex] \frac{1}{2} g t^{2} [/tex]
H=3.9m/s*[tex] \sqrt{12} + \frac{1}{2} *10* \sqrt{12}^{2} [/tex]
H=13.51+60
=73.51 m