<h2>
Answer:0.875

</h2>
Explanation:
Momentum is defined as the product of mass of an object and the velocity of that object.
Let
be the mass of the object.
Let
be the velocity of the object.
Let
be the momentum of the object.
Given that 



Velocity = displacement (distance)/time
v=80m/4s
v=20m/s
velocity = 20 meters per second
A. pure water ....................