I think your in the wrong section kid. This should be in Earth and Space Science.
Answer:
120 Ns
Explanation:
The impulse exerted on an object is given by:

where
F is the force applied
t is the time taken
In this problem, we have:
F = 40 N
t = 3.0 s
So, the impulse acting on the boat is

The answer is <em>B. 5/4</em> or <em>1.25</em>