I've found the missing details of this task, so I can help you out:
First: keep in mind that the value of vertical motion does not depend on horizontal motion. The task asks you to figure
the amount of time for a drop of water to fall 1 meter from Isabella's hand and check whether this time is enough for the water to reach the boy.
Solution for vertical motion:

For horizontal motion:

Now you can see that this amount of time is not enough.