Answer
Please see the work below.
Work Step by Step
We know that
$t=\sqrt{\frac{2h}{g}}$
$t=\sqrt{\frac{2(1.6-0.93)}{9.8}}=0.3698s$
Now we can find the horizontal speed of the water as
$v=\frac{x}{t}$
We plug in the known values to obtain:
$v=\frac{2.1}{0.3698}=5.7\frac{m}{s}$
