We have, the depth of the river means height = 3 m
the width of the river = 40 m
Velocity of the river = 2 km/hour
So, it means in one hour water in river can flow = 2 km
And in 60 minutes = 2000 m
So, in 1 minute water can flow
==m So, for 1 minute river length
=m ∴ Volume of water falling in a sea = volume of the river which is like cuboid
=×3×40 =4000m3 or 40,00,000 litres