To calculate the time it takes Amelia to complete a race of 600 meters at an average speed of 8 meters per second, you can use the formula:
\[ \text{Time} = \frac{\text{Distance}}{\text{Speed}} \]
Plugging in the values:
\[ \text{Time} = \frac{600 \text{ meters}}{8 \text{ meters/second}} = 75 \text{ seconds} \]
Thus, the answer is:
a 75 seconds.