<span>A.
The model of the atom evolved as scientists have made new discoveries.</span>
Answer:
The force of the nail pushing in the opposite direction
Given
Car 1
m1 = 1300 kg
v1 = 20 m/s
m2 = 900 kg
v2 = -15 m/s
(Negative sign shows that direction of car 2 is opposite to car 1)
Procedure
As per the conservation of linear momentum, "The total momentum of the system before the collision must be equal to the total momentum after the collision". And this applies to the perfectly inelastic collision as well. Then the expression is,

Thus, we can conclude that the speed and direction of the cars after the impact is 5.68 m/s towards the first car.
Answer:
Resistance to electrical currents
Explanation:
Conductors have low resistance to electrical currents, and are used to "conduct" the flow of electricity.
Insulators have very high resistance and are used to protect us from the flow of electricity.
Because it demonstrates the relationship between a body and the forces acting upon it, and its motion in response to those forces. [Hope that helps]