Final answer:
The acceleration of the fish is -1 m/s².
Step-by-step explanation:
The graph shows the speed of a fish over time. To calculate the acceleration, we need to find the change in speed over the change in time. Looking at the graph, we can see that the speed starts at 10 m/s and ends at 9 m/s. The time interval is 8-7 = 1 second.
Acceleration = (change in speed) / (change in time) = (9 m/s - 10 m/s) / 1 s = -1 m/s²
Therefore, the acceleration of the fish is -1 m/s².