Answer
$v=10.9m/s$
Work Step by Step
$x=v_{x}t=(vcos\theta )t$
$t=\frac{x}{vcos\theta}$
$h=ut+\frac{1}{2}gt^{2}=vsin\theta\frac{x}{vcos\theta}-\frac{g(\frac{x}{vcos\theta})^{2}}{2}$
Therefore, $v=\sqrt \frac{gx^{2}}{2(cos\theta)^{2}(xtan\theta-h)}$
Since, x=6.02m, $\theta=25^{\circ}$, h=1m,
$v=10.9m/s$