Final answer:
To solve the problem, we use Newton's second law of motion and calculate the total force resisting the motion of the car and trailer. In part (b), we find the force in the hitch between the car and trailer.
Step-by-step explanation:
To solve this problem, we can use Newton's second law of motion, which states that the net force acting on an object is equal to the mass of the object multiplied by its acceleration.
In this case, the car and the trailer are considered as one system, so the total mass is the sum of their masses. The total force resisting the motion can be found by multiplying the total mass by the acceleration.
In part (a) of the question, the total force resisting the motion is equal to the mass of the car and trailer multiplied by their acceleration. In part (b), we need to find the force in the hitch between the car and the trailer.
Since 80% of the resisting forces are experienced by the boat and the trailer, we can calculate the force in the hitch by multiplying the total force resisting the motion by 0.8.
The answers to part (a) and part (b) are left as an exercise.