Final answer:
The question is a physics problem related to Newton's second law of motion, addressing the calculation of the acceleration of rockets. Specific data from each student's rocket is missing, but acceleration can generally be calculated using force and mass data from given examples.
Step-by-step explanation:
The student's question regarding which rocket had the greatest acceleration appears to be part of a physics problem involving Newton's second law of motion and the calculation of acceleration. Without the specific data for each of the four student's rockets, we cannot directly calculate which one had the greatest acceleration. However, based on the reference information provided, we can understand how to calculate acceleration using the force and mass.
For instance, using the reference data from problem 7(a), the acceleration 'a' of the rocket sled can be calculated with Newton's second law (F = ma), where F is the net force applied to an object, m is its mass, and a is its acceleration. To find the net force, you subtract the force of friction from the thrust, then divide by the mass of the sled. In this case, that would be (2.4 × 10⁴ N - 650 N) / 2100 kg.
The part (b) of the same question touches on the concept that the total thrust is not simply divided evenly amongst the number of rockets because the mass and the force of friction remain constant regardless of how many rockets are burning.