Final answer:
The average speed of a car between 3 seconds and 6 seconds cannot be determined without knowing the distance covered in that time. The average speed is calculated as total distance divided by total time.
Step-by-step explanation:
To calculate the average speed of the car between 3 seconds and 6 seconds, we would need to know the distance covered by the car during this time interval. Since such specifics are not provided in the details you've shared, we cannot determine the average speed. Usually, if the distance traveled is known, the average speed can be calculated using the formula:
Average speed = Total distance / Total time
In this context, without the distance, it is impossible to choose between options a, b, c, or d. However, if this information was part of a larger data set or word problem, please ensure to provide the entire problem statement for an accurate calculation.