Bohr is the scientist you are looking for my friend...;)
As per Newton's III law we can say that
Force applied by object 1 on object 2 is always equal in magnitude and opposite in direction of the force that object 2 apply on object 1.
So we can say it as

now here above question is based upon the same
if a bag of vegetables applied a force F = 22.5 N of the surface stand the the same surface will apply same magnitude of force in opposite direction on the vegetables bag
So our answer will be F = 22.5 N (upwards).
The acceleration of the car is solved by subtracting the initial speed from the final speed then dividing the result by the elapsed time.
initial speed = 72 km/hr = 20 m/s
final speed = 0 m/s
elapsed time = 5 seconds
acceleration = (0 m/s – 20 m/s) / 5 s
acceleration = - 20m/s / 5 s
acceleration = -4 m/s^2