Answer :
Horizontal component of ball, u = 0 m/s.
Height from which it thrown, h = 62 m.
By equation of motion :
[tex]s=ut+\dfrac{at^2}{2}[/tex]
Putting all given equation, we get :
[tex]62=0\times t+\dfrac{10t^2}{2}\\\\t=\sqrt{12.4}\ s\\\\t = 3.52\ s[/tex]
Therefore, time taken is 3.52 s.
Hence, this is the required solution.