Define the apparent cubic expansivity of a liquid

THE APPARENT CUBIC EXPANSIVITY OF A LIQUID : is defined as the increase in volume per unit volume per unit rise in temperature when the liquid is heated in an expansible vessel.

here we know that ball will drop down by total distance 3.2 m

so here we know that

now using kinematics

now in the same time it will cover horizontal distance of 0.75 m

so speed of the ball will be