Figure 9 shows part of the free body diagram for the boat - AQA - GCSE Physics - Question 6 - 2018 - Paper 1

To complete the free body diagram for the boat, you need to draw the following forces acting on the boat:

1. Weight (W) - This force acts downwards and can be represented as a downward arrow labelled "Weight". Given that the weight of the boat is 25 kN, the arrow should be of appropriate length to represent this magnitude.

2. Upthrust (Buoyant Force) - This force acts upwards and should be indicated by an arrow of equal size as the weight arrow. Label this arrow as "Upthrust".

3. Other Forces (if necessary) - If the problem mentioned other forces, such as tension or buoyancy, these should also be represented but from the question details, only the weight and upthrust need to be drawn.