Answer
The tension in the hitch is $160N$.
Work Step by Step
The mass of the boat and the trailer $M=410kg$
a) Find the acceleration of the car:
We have $v_0=0$, $v=11m/s$ and $\Delta t=28s$. Therefore, $$a=\frac{\Delta v}{\Delta t}=\frac{11}{28}=0.39m/s^2$$
b) The tension $T$ in the hitch acts as the pulling force that pulls the trailer and the boat behind and gives them acceleration. Since we do not care about friction here, $T$ is the only force involved in the movement. $$T=Ma=410\times0.39=160N$$
