I'm thinking the answer would be D.
I hope this helps ☺ Let me know if you have any others
Answer:4500 N
Explanation:
Given
mass of truck 
mass of car
as the car push the ground with a force of 4500 N so the force on the truck should also be 4500 N as they all the force is transmitted to push the truck
and their acceleration is

Answer:
2 m/s².
Explanation:
The forces acting on the crate have been shown in the figure below.
Net force acting on the crate in the horizontal direction = 400 - 250 = 150 N towards right.
For the forces of vertical direction we can write,
Normal force = 150 + Mg = 150 + 250 = 400 N (here g = 10 m/s² have been taken)
The magnitude of frictional force that will act on the crate = μ × Normal force
So, Frictional force = 0.25 × 400 = 100 N
Thus, the net force that will cause acceleration in the crate will be
Force in the right direction - frictional force
= 150 - 100 = 50 N
As we know,
Acceleration =
=
= 2 m/s²
So, the net acceleration in the crate will be 2 m/s².
<span>from a trough to the rest position and from a crest to the rest position.
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