A ball thrown upward from the top of a tower with speed `v` reaches the ground in `t_(1)` sec. If this ball is thrown downward from the top of the same tower with speed `v` it reaches the ground in `t_(2)` sec. In what time, the ball shall reach the grouned, if it is allowed to fall freely under gravity from the top of the tower?

Options

A. `(t_1 + t_2)/2`
B. `(t_1 - t_2)/2`
C. `sqrtt_1 t_2`
D. `t_1 + t_2`