The independent variable is how much weight you add to the boat.
The dependent variable is: Did it or did it not sink yet ?
Answer:
100N
Explanation:
Newton's third law states that whenever an object exerts a force on a second object, it exerts a force of equal magnitude and direction but in the opposite direction on the first. It is often stated as follows: Each action always opposes an equal but opposite reaction.
The subject 1 of 100kg is making a force F, to move an object from 50Kg to 2m / s ^ 2. This Force the object of 50Kg will reflect it in the opposite direction by Newton's third law.
Once the parameter of the force that both are experiencing is clarified, Newton's second law is applied to their respective calculation.

That is the force the boy exert on the man during the shove.