Step-by-step explanation:
It is given that,
Mass of car A,

Mass of car B,

In a performance test, each of two cars takes 9.0 s to accelerate from rest to 28 m/s. Their acceleration is given by :


a = 3.12 m/s²
(a) The net force of car A,



(b) The net force of car B,



Hence, this is the required solution.